Interplay between drought and plant viruses co-infecting melon plants.

Drought affects crops directly, and indirectly by affecting the activity of insect pests and the transmitted pathogens. Here, we established an experiment with well-watered or water-stressed melon plants, later single infected with either cucumber mosaic virus (CMV: non-persistent), or cucurbit aphid-borne yellow virus (CABYV: persistent), or both CMV and CABYV, and mock-inoculated control. We tested whether i) the relation between CMV and CABYV is additive, and ii) the relationship between water stress and virus infection is antagonistic, i.e., water stress primes plants for enhanced tolerance to virus infection. Water stress increased leaf greenness and temperature, and reduced leaf water potential, shoot biomass, stem dimensions, rate of flowering, CABYV symptom severity, and marketable fruit yield. Virus infection reduced leaf water potential transiently in single infected plants and persistently until harvest in double-infected plants. Double-virus infection caused the largest and synergistic reduction of marketable fruit yield. The relationship between water regime and virus treatment was additive in 12 out of 15 traits at harvest, with interactions for leaf water content, leaf:stem ratio, and fruit set. We conclude that both virus-virus relations in double infection and virus-drought relations cannot be generalized because they vary with virus, trait, and plant ontogeny.

Anthropogenic land-use change decreases pollination and male and female fitness in terrestrial flowering plants.

BACKGROUND AND AIMS: The majority of the earth's land area is currently occupied by humans. Measuring how terrestrial plants reproduce in these pervasive environments is essential for understanding their long-term viability and their ability to adapt to changing environments. METHODS: We conducted hierarchical and phylogenetically-independent meta-analyses to assess the overall effects of anthropogenic land-use changes on pollination, and male and female fitness in terrestrial plants. KEY RESULTS: We found negative global effects of land use change (i.e., mainly habitat loss and fragmentation) on pollination and on female and male fitness of terrestrial flowering plants. Negative effects were stronger in plants with self-incompatibility (SI) systems and pollinated by invertebrates, regardless of life form and sexual expression. Pollination and female fitness of pollination generalist and specialist plants were similarly negatively affected by land-use change, whereas male fitness of specialist plants showed no effects. CONCLUSIONS: Our findings indicate that angiosperm populations remaining in fragmented habitats negatively affect pollination, and female and male fitness, which will likely decrease the recruitment, survival, and long-term viability of plant populations remaining in fragmented landscapes. We underline the main current gaps of knowledge for future research agendas and call out not only for a decrease in the current rates of land-use changes across the world but also to embark on active restoration efforts to increase the area and connectivity of remaining natural habitats.

Morphological diversity and fruit production of wild Salacia kraussii (Celastraceae) on the Northern Coast of KwaZulu-Natal, South Africa.

This study aimed to assess morphological diversity within Salacia kraussii, a fruit and medicinal wild plant species, based on morphological features and compared the fruit production among morphological types (morphotype) that naturally occur on the northern coast of KwaZulu-Natal. Following one species plant survey, a description of the qualitative morphological features revealed that S. kraussii individuals mainly differed in their leaf shapes, having elliptic, oblong, or obovate leaves. That led us to the identification of three morphotypes, namely Salacia kraussii 'elliptic', Salacia kraussii 'oblong' and Salacia kraussii 'obovate'. The analysis of variance (one-way ANOVA) of plant quantitative features indicated that plant height, stem diameter, branch number, leaf number and area, and fruit number were significantly different between plants from different sites (p-values < 0.05) and morphotypes (p-values < 0.01). Generally, S. kraussii grows in KwaZulu-Natal as a suffrutex with many stems and exhibits short plant height, small stem diameter, branches, and little foliage per stem. The average fruit number recorded per plant stem was likewise few. Plants growing in Sikhalasenkosi (site1) dominated in average plant height (35.58 cm), leaf number (45), number of branches (4), and number of fruits (5). Plants with elliptic leaves constantly dominated in average plant height (34.45 cm), foliage (36 leaves of 16.29 cm2 each), number of branches (4), and number of fruits (5). A few plants exhibited a strong vegetative vigor and produced more than 20 fruits. There was a highly positive correlation (CC = 0.8) between plant height and leaf number, branch number and leaf number, and branch number and fruit number. However, a negative correlation (CC = -0.1) was recorded between the leaf area and stem diameter. Overall, the study showed wide morphological diversity and fruit production within and between populations of S. kraussii, on the northern coast of KwaZulu-Natal.

Performance of 'Gala Select' and 'Fuji Suprema' grafted on Geneva series rootstocks under fallow land and replanting conditions in southern Brazil.

Background: Rootstocks less vigorous are among the most crucial management techniques to modernize fruit cultivation. Replanting with fallow land has become necessary due to a lack of land to establish new orchards. Objective: The aim of this study is to determine the effect of various rootstocks of the American Geneva® series on the yield performance of the apple (Malus domestica Borkh) cultivars 'Gala Select' and 'Fuji Suprema' under replanting conditions in southern Brazil. Methods: After two years of fallow land, the experiments were initiated in 2017 and conducted during the 2018, 2019, 2020, and 2021 growing seasons in Painel and Caxias do Sul municipalities at the Santa Catarina and the Rio Grande do Sul State, respectively. The 'Gala Select' and 'Fuji Suprema' were grafted onto the G.202, G.814, G.210, and G.213 Geneva series rootstocks in a tall spindle training system using a randomized complete block design with four replicates. Principal component analysis (PCA) was used to assess the interrelationship among the variable's vigor, productivity, and fruit quality. Results: The PCA result showed significant differences in vigor, productivity, and fruit quality when the G.210 and G.213 and G.814 and G.213 Geneva series rootstocks were used in combination with Gala Select and Fuji Suprema cultivars, respectively. The PCA analysis clustered all cultivar/rootstock combinations into two groups, based on their vigor and productivity and the yield performance and fruit quality data, that differed significantly among combinations and regions. The 'Gala Select'/G.202 and 'Fuji Suprema'/G.213 combinations were less vigorous than the 'Gala Select'/G.210 and 'Fuji Suprema'/G.814 combinations. However, 'Gala Select'/G.210 (semi-dwarfing) and G.213 (dwarfing) are the combinations with high yield performance, productive efficiency and fruit quality, being more reliable to the producer, and less vigorous, resulting in lower labor costs under replating conditions, with two years of fallow land, from 2018 until 2021 growing seasons.

Dataset from RNAseq analysis of bud differentiation in Ficus carica.

The presented data regards the transcriptome profiling and differential analysis with RNA-Seq approach with the following goals: de novo transcriptome assembly and genome annotation of Ficus carica and the differential expression analysis of parthenocarpic and non-partenocarpic varieties in order to identify candidate genes for the production of seedless fig. Two fig varieties Dottato and Petrelli and the caprifig were grown at the fig repository at the 'P. Martucci' experimental station in Valenzano (Bari) of University of Bari 'Aldo Moro'. The data included: RNA-seq data obtained from fruits of parthenocarpic and non-parthenocarpic varieties, gene expression in the different genetic materials; genes up and down regulated. The data in this article support information presented in the research article "I. Marcotuli, A. Mazzeo, P. Colasuonno, R. Terzano, D. Nigro, C. Porfido, A. Tarantino, R. Aiese Cigliano, W. Sanseverino, A. Gadaleta, G. Ferrara, Fruit Development in Ficus carica L.: Morphological and Genetic Approaches to Fig Buds for an Evolution From Monoecy Toward Dioecy. Front. Plant Sci.(2020) 11:1208. doi: 10.3389/fpls.2020.01208.

Metabolomics and genetics of reproductive bud development in Ficus carica var. sativa (edible fig) and in Ficus carica var. caprificus (caprifig): similarities and differences.

In figs, reproductive biology comprises cultivars requiring or not pollination, with female trees (edible fig) and male trees (caprifig) bearing different types of fruits. Metabolomic and genetic studies may clarify bud differentiation mechanisms behind the different fruits. We used a targeted metabolomic analysis and genetic investigation through RNA sequence and candidate gene investigation to perform a deep analysis of buds of two fig cultivars, 'Petrelli' (San Pedro type) and 'Dottato' (Common type), and one caprifig. In this work, proton nuclear magnetic resonance (1H NMR-based metabolomics) has been used to analyze and compare buds of the caprifig and the two fig cultivars collected at different times of the season. Metabolomic data of buds collected on the caprifig, 'Petrelli', and 'Dottato' were treated individually, building three separate orthogonal partial least squared (OPLS) models, using the "y" variable as the sampling time to allow the identification of the correlations among metabolomic profiles of buds. The sampling times revealed different patterns between caprifig and the two edible fig cultivars. A significant amount of glucose and fructose was found in 'Petrelli', differently from 'Dottato', in the buds in June, suggesting that these sugars not only are used by the ripening brebas of 'Petrelli' but also are directed toward the developing buds on the current year shoot for either a main crop (fruit in the current season) or a breba (fruit in the successive season). Genetic characterization through the RNA-seq of buds and comparison with the literature allowed the identification of 473 downregulated genes, with 22 only in profichi, and 391 upregulated genes, with 21 only in mammoni.

Growth, Flowering, and Fruit Production of Strawberry 'Albion' in Response to Photoperiod and Photosynthetic Photon Flux Density of Sole-Source Lighting.

Beyond producing leafy greens, there is a growing interest in strawberry production on indoor vertical farms. Considering that sole-source lighting is one of the most important components for successful indoor crop production, we investigated how photosynthetic photon flux density (PPFD) and the photoperiod of sole-source lighting affected plant growth, flowering, and fruit production in strawberry 'Albion.' Bare-rooted strawberry plants were grown in deep water culture hydroponics inside an indoor vertical farm at 21 °C under white + blue + red light-emitting diodes at a PPFD of 200, 300, or 450 µmol∙m-2∙s-1 with a 12-h or 16-h photoperiod. Under both photoperiods, increasing PPFD from 200 to 450 µmol∙m-2∙s-1 linearly increased crown diameter by 18-64%, shoot fresh and dry mass by 38-80%, and root fresh and dry mass by 19-48%. Under a PPFD ≥ 300 µmol∙m-2∙s-1, root fresh and dry biomass increased by 95-108% and 41-44%, respectively, with an increasing photoperiod from 12 to 16 h. In addition, increasing the photoperiod from 12 to 16 h accelerated flowering by 17-21 days under a PPFD ≥ 300 µmol∙m-2∙s-1 and first fruit harvest by 17 days at a PPFD of 450 µmol∙m-2∙s-1. Regardless of PPFD, strawberry fruit production (g·m-2·month-1) increased by 372-989% under a 16-h photoperiod in comparison to under a 12-h photoperiod. In contrast, there was little effect of PPFD on fruit production. Our results suggest that increasing the PPFD or photoperiod can increase strawberry plant growth, but increasing the photoperiod can have a dominant effect on increasing early fruit production in strawberry 'Albion'.

Altered volatile emission of pear trees under elevated atmospheric CO2 levels has no relevance to pear psyllid host choice.

The impact of climate change drivers on cultivated plants and pest insects has come into research focus. One of the most significant drivers is atmospheric carbon dioxide, which is converted into primary plant metabolites by photosynthesis. Increased atmospheric CO2 concentrations therefore affect plant chemistry. The chemical composition of non-volatile and volatile organic compounds of plants is used by insects to locate and identify suitable host plants for feeding and reproduction. We investigated whether elevated CO2 concentrations in the atmosphere affect the plant-pest interaction in a fruit crop of high economic importance in Europe. Therefore, potted pear trees were cultivated under specified CO2 conditions in a Free-Air Carbon dioxide Enrichment (FACE) facility at Geisenheim University in Germany for up to 14 weeks, beginning from bud swelling. We compared emitted volatiles from these pear trees cultivated for 7 and 14 weeks under two different CO2 levels (ambient: ca. 400 ppm and elevated: ca. 450 ppm CO2) and their impact on pest insect behavior. In total, we detected and analyzed 76 VOCs from pear trees. While we did not detect an overall change in VOC compositions, the relative release of single compounds changed in response to CO2 increase. Differences in VOC release were inconsistent over time (phenology stages) and between study years, indicating interactions with other climate parameters, such as temperature. Even though insect-plant interaction can rely on specific volatile compounds and specific mixtures of compounds, respectively, the changes of VOC patterns in our field study did not impact the host choice behavior of C. pyri females. In olfactometer trials, 64% and 60% of the females preferred the odor of pear trees cultivated under elevated CO2 for 7 and 14 weeks, respectively, over the odor from pear trees cultivated under ambient CO2. In binary-choice oviposition assays, C. pyri females laid most eggs on pears during April 2020; on average, 51.9 (± 51.3) eggs were laid on pears cultivated under eCO2 and 60.3 (± 48.7) eggs on aCO2.

Irrigation area, efficiency and water storage mediate the drought resilience of irrigated agriculture in a semi-arid catchment.

We examined the effects of hydrological variables such as irrigation area, irrigation efficiency and water storage on the resilience of (mostly commercial) irrigated agriculture to drought in a semi-arid catchment in South Africa. We formulated a conceptual framework termed 'Water, Efficiency, Resilience, Drought' (WERD) and an accompanying spreadsheet model. These allow the resilience of irrigated agriculture to drought to be analysed via water accounts and a key resilience indicator termed Days to Day Zero (DDZ). This represents the number of days that a pre- and within-drought supply of catchment water available to irrigation is withdrawn down to zero in the face of a prolonged drought. A higher DDZ (e.g. >300 days) indicates greater resilience whilst a lower DDZ (e.g. <150 days) signals lower resilience. Drought resilience arises through land and water management decisions underpinned by four types of resilience capacities; absorptive, adaptive, anticipative and transformative. For the case study, analyses showed that irrigators, with currently approximately 23,000 ha under irrigation, have historically absorbed and adapted to drought events through construction of water storage and adoption of more efficient irrigation practices resulting in a DDZ of 260 days. However, by not fully anticipating future climate and water-related risks, irrigators are arguably on a maladaptive pathway resulting in water supply gains, efficiency and other practices being used to increase irrigation command areas to 28,000 ha or more, decreasing their capacity to absorb future droughts. This areal growth increases water withdrawals and depletion, further stresses the catchment, and reduces future DDZs to approximately 130 days indicating much lower drought resilience. Our approach, supported by supplementary material, allows stakeholders to understand the resilience consequences of future drought in order to; reconcile competition between rising water demands, consider new water storage; improve agricultural and irrigation planning; and enhance catchment governance.

Assessment of variability in nutritional quality of wild edible fruit of Monotheca buxifolia (Falc.) A. DC. Along the altitudinal gradient in Pakistan.

The fruit of Monotheca buxifolia is among the underutilized wild edible fruits that grows in Hindukush and Suleiman range mountains of Pakistan. Mountain communities consume this wild fruit as a food, medicine and it provides an important source of income. In this study, we aimed to investigate the total yield and the effect that altitude plays on its proximate composition and mineral contents as determined through phytochemical screening of this economically important wild fruit. Our results indicate a significant increase in the total fruit yield with increasing trunk diameter (R2 = 0.98), height (R2 = 0.95) and cover (R2 = 0.92). The proximate composition shows that the crude fat and carbohydrate contents of Monotheca fruit significantly varies (P < 0.05) along the altitudinal gradient. Similarly, ANOVA followed by post hoc Tukey HSD, further confirms the variation (P < 0.01) in moisture contents of the fruit. Dry matter ranged from 95.28 ± 4.64 to 108 ± 3.70 g kg- 1 of the fruit's edible portion, while protein contents varied between 17.16 % and 20.44 %. The fruits were found to be rich in minerals containing sizeable amounts of potassium, iron, phosphorus, sodium, nitrogen, magnesium, and copper. Significant difference was observed in the nitrogen (P < 0.01), potassium (P < 0.05) and sodium (P < 0.05) contents of the fruit along the altitudinal gradient. Similarly, tannins, flavonoids, saponins, reducing sugars, terpenoids, anthraquinones, and cardiac glycosides, were the most prominent chemicals found in Monotheca fruit. It was concluded that Monotheca fruit is a good source of carbohydrates, proteins, macro and micro-nutrients which fluctuated along the altitudinal gradient.

Tissue culture coupled with a gas exchange system offers new perspectives on phenotyping the developmental biology of Solanum lycopersicum L. cv. 'MicroTom'.

Solanum lycopersicum L. cv. 'Microtom' (MicroTom) is a model organism with a relatively rapid life cycle, and wide library of genetic mutants available to study different aspects of plant development. Despite its small stature, conventional MicroTom research often requires expensive growth cabinets and/or expansive greenhouse space, limiting the number of experimental and control replications needed for experiments, and can render plants susceptible to pests and disease. Thus, alternative experimental approaches must be devised to reduce the footprint of experimental units and limit the occurrence problematic confounding variables. Here, tissue culture is presented as a powerful option for MicroTom research that can quell the complications associated with conventional MicroTom research methods. A previously established, non-invasive, analytical tissue culture system is used to compare in vitro and conventionally produced MicroTom by assessing photosynthesis, respiration, diurnal carbon gain, and fruit pigments. To our knowledge, this is the first publication that measures in vitro MicroTom fruit pigments and compares diurnal photosynthetic/respiration responses to abiotic factors between in vitro and ex vitro MicroTom. Comparable trends would validate tissue culture as a new benchmark method in MicroTom research, as it is like Arabidopsis, allowing replicable, statistically valid, high throughput genotyping and selective phenotyping experiments. Combining the model plant MicroTom with advanced tissue culture methods makes it possible to study bonsai-style MicroTom responses to light, temperature, and atmospheric stimuli in the absence of confounding abiotic stress factors that would otherwise be unachievable using conventional methods.

Determining Reproductive Parameters, which Contribute to Variation in Yield of Olive Trees from Different Cultivars, Irrigation Regimes, Age and Location.

Olive (Olea europaea L.) trees can reach a very old age and still bear fruit. Although traditional groves are planted at low density and are rainfed, many newer groves are planted at higher densities and irrigated. As expected, initial yields per area are larger in high density plantations, yet some farmers claim they experience a reduction in productivity with grove age, even in well maintained trees. In order to test the accuracy of this claim and its underlying cause, we measured several productivity parameters in selected branches of trees in seven sites differing in cultivar ('Barnea' or 'Souri'), location and irrigation regime (rainfed or irrigated) for two consecutive years. For each site (cultivar/location/regime), we compared neighboring groves of different ages, altogether 14 groves. There was no consistent reduction in productivity in older groves. Differences in productivity between irrigated cultivars were mostly due to variation in the percentage of inflorescences that formed fruit. Several parameters were higher in irrigated, compared to rainfed 'Souri'. Differences in productivity between years within the same grove was mostly due to variation in the percentage of nodes forming inflorescences. We studied the expression of OeFT2 encoding a FLOWERING LOCUS T protein involved in olive flower induction in leaves of trees of different ages, including juvenile seedlings. Expression increased during winter in mature trees and correlated with the percentage of inflorescences formed. The leaves of juvenile seedlings expressed higher levels of two genes encoding APETALA2-like proteins, potential inhibitors of OeFT2 expression. The buds of juvenile seedlings expressed higher levels of OeTFL1, encoding a TERMINAL FLOWER 1 protein, a potential inhibitor of OeFT2 function in the meristem. Our results suggest that olives, once past the juvenile phase, can retain a similar level of productivity even in densely planted well maintained groves.

Conservative seed fertility maintains hermaphrodites in gynodioecious Daphne jezoensis: a test of the sex-differential plasticity hypothesis.

Gynodioecy is assumed to be an evolutionary transition from hermaphroditism to dioecy. However, if hermaphrodites can better flexibly regulate seed production depending on resource availability than females, i.e. sex-differential plasticity (SDP), gynodioecy can be a stable state. In the gynodioecious shrub Daphne jezoensis, hermaphrodites generally exhibit low seed fertility and largely act as males. We examined the SDP hypothesis and the cost of fruit production to clarify why D. jezoensis did not evolve into unisexual morphs. We evaluated the size and resource dependency of reproduction in field experiments by manipulating soil nutrient and light conditions. We compared the plant size and pollen production among females, fruiting hermaphrodites and non-fruiting hermaphrodites. We then analysed the effect of current fruit production on subsequent flower production, i.e. the cost of fruit production. The fruiting ability was independent of plant size and resource availability in both sexual phenotypes, indicating the absence of SDP in D. jezoensis. Hermaphrodites produced larger-sized pollen and allocated more resources to pollen production in the non-fruiting year than in the fruiting year. In contrast, the cost of fruit production was not revealed for either sexual phenotype, even in the absence of pollen limitation, and even when fruit production was maximized. SDP could not explain the maintenance of hermaphrodites in D. jezoensis. Alternatively, the lower cost of fruit production in hermaphrodites due to their potentially low fruiting ability may hinder the evolutionary shift to dioecy.

Application of Convolutional Neural Network-Based Detection Methods in Fresh Fruit Production: A Comprehensive Review.

As one of the representative algorithms of deep learning, a convolutional neural network (CNN) with the advantage of local perception and parameter sharing has been rapidly developed. CNN-based detection technology has been widely used in computer vision, natural language processing, and other fields. Fresh fruit production is an important socioeconomic activity, where CNN-based deep learning detection technology has been successfully applied to its important links. To the best of our knowledge, this review is the first on the whole production process of fresh fruit. We first introduced the network architecture and implementation principle of CNN and described the training process of a CNN-based deep learning model in detail. A large number of articles were investigated, which have made breakthroughs in response to challenges using CNN-based deep learning detection technology in important links of fresh fruit production including fruit flower detection, fruit detection, fruit harvesting, and fruit grading. Object detection based on CNN deep learning was elaborated from data acquisition to model training, and different detection methods based on CNN deep learning were compared in each link of the fresh fruit production. The investigation results of this review show that improved CNN deep learning models can give full play to detection potential by combining with the characteristics of each link of fruit production. The investigation results also imply that CNN-based detection may penetrate the challenges created by environmental issues, new area exploration, and multiple task execution of fresh fruit production in the future.

Climate influence on plant-pollinator interactions in the keystone species Vaccinium myrtillus.

Climate change is altering the world's ecosystems through direct effects of climate warming and precipitation changes but also indirectly through changes in biotic interactions. For instance, climate-driven changes in plant and/or insect communities may alter plant-pollinator interactions, thereby influencing plant reproductive success and ultimately population dynamics of insect-pollinated plants. To better understand how the importance of insect pollination for plant fruit set varies with climate, we experimentally excluded pollinators from the partly selfing keystone species Vaccinium myrtillus along elevational gradients in the forest-tundra ecotone in central Norway. The study comprised three mountain areas, seven elevational gradients spanning from the climatically relatively benign birch forest to the colder alpine areas above the tree line, and 180 plots of 1 × 1 m, with experimental treatments allocated randomly to plots within sites. Within the experimental plots, we counted the number of flowers of V. myrtillus and counted and weighed all fruits, as well as seeds for a selection of fruits. Excluding pollinators resulted in lower fruit production, as well as reduced fruit and seed mass of V. myrtillus. In the alpine sites pollinator exclusion resulted in 84% fewer fruits, 50% lower fruit weight, and 50% lower seed weight compared to control conditions. Contrary to our expectations, the negative effect of pollinator exclusion was less pronounced in the forest compared to alpine sites, suggesting that the importance of insect pollination for seed production is lower at low elevations. Our findings indicate that the keystone species V. myrtillus is relatively robust to changes in the pollinator community in a warmer climate, thereby making it less vulnerable to climate-driven changes in plant-pollinator interactions.

Impact of ambient temperature, precipitation and seven years of experimental warming and nutrient addition on fruit production in an alpine heath and meadow community.

Alpine and polar regions are predicted to be among the most vulnerable to changes in temperature, precipitation, and nutrient availability. We carried out a seven-year factorial experiment with warming and nutrient addition in two alpine vegetation communities. We analyzed the relationship between fruit production and monthly mean, maximum, and min temperatures during the fall of the pre-fruiting year, the fruiting summer, and the whole fruit production period, and measured the effects of precipitation and growing and thawing degree days (GDD & TDD) on fruit production. Nutrient addition (heath: 27.88 ± 3.19 fold change at the end of the experiment; meadow: 18.02 ± 4.07) and combined nutrient addition and warming (heath: 20.63 ± 29.34 fold change at the end of the experiment; meadow: 18.21 ± 16.28) increased total fruit production and fruit production of graminoids. Fruit production of evergreen and deciduous shrubs fluctuated among the treatments and years in both the heath and meadow. Pre-maximum temperatures had a negative effect on fruit production in both communities, while current year maximum temperatures had a positive impact on fruit production in the meadow. Pre-minimum, pre-mean, current mean, total minimum, and total mean temperatures were all positively correlated with fruit production in the meadow. The current year and total precipitation had a negative effect on the fruit production of deciduous shrubs in the heath. GDD had a positive effect on fruit production in both communities, while TDD only impacted fruit production in the meadow. Increased nutrient availability increased fruit production over time in the high alpine plant communities, while experimental warming had either no effect or a negative effect. Deciduous shrubs were the most sensitive to climate parameters in both communities, and the meadow was more sensitive than the heath. The difference in importance of TDD for fruit production may be due to differences in snow cover in the two communities.

Contrasting effects of nectar yeasts on the reproduction of Mediterranean plant species.

PREMISE: Yeasts are often present in floral nectar and can influence plant fitness directly (independently of pollinators) or indirectly by influencing pollinator visitation and behavior. However, few studies have assessed the effect of nectar yeasts on plant reproductive success or compared effects across different plant species, limiting our understanding of the relative impact of direct vs. indirect effects. METHODS: We inoculated the nectar of six plant species in the field with the cosmopolitan yeast Metschnikowia reukaufii to analyze the direct and indirect effects on female reproductive success over 2 years. The pollinator assemblage for each species was recorded during both flowering years. RESULTS: Direct yeast effects on female fecundity were statistically nonsignificant for all plant species. There were significant indirect, pollinator-mediated effects on fruit production and seed mass for the two species pollinated almost exclusively by bumblebees or hawkmoths, with the direction of the effects differing for the quantity- and quality-related fitness components. There were no consistent effects of the yeast on maternal fecundity for any of the species with diverse pollinator assemblages. CONCLUSIONS: Effects of M. reukaufii on plant reproduction ranged from negative to neutral or positive depending on the plant species. The among-species variation in the indirect effects of nectar yeasts on plant pollination could reflect variation in the pollinator community, the specific microbes colonizing the nectar, and the order of microbial infection (priority effects), determining potential species interactions. Elucidating the nature of these multitrophic plant-pollinator-microbe interactions is important to understand complex processes underlying plant pollination.

Using an asymmetrical technique to assess the impacts of CO2 emissions on agricultural fruits in Pakistan.

Human activities such as deforestation and cultivation contribute to the accumulation of carbon dioxide in the environment. Methane is emitted by energy exploration, coal mining, natural gas spills, waste, and waste dumps. Methane generated by such greenhouse gases has significantly contributed to the climate change and global warming. However, the most significant contributor to climate change and global warming is the use of fossil fuels. These fuels contribute to ozone depletion and global warming by emitting greenhouse gases into the atmosphere. The current study key objective was to determine the CO2 emission effect to key fruit production in Pakistan by taking time series annual data varies from 1970 to 2019. A non-linear autoregressive distributed lag model (NARDL) was employed to check the variables linkages. The consequences of short- and long-run estimates expose that the positive and adverse shocks of citrus fruit create expressively to upsurge the CO2 emission. Similarly, the positive and negative shocks of mango fruit expose an adverse interaction to CO2 emission. The positive shock of apple fruit has constructive but negative shock expose and adverse linkage to CO2 emission. Further, banana fruit also exposes a negative but constructive via positive shock linkage to CO2 emission. Moving towards the apricot fruit production that exposed a constructive linkage via positive and negative shocks to CO2 emission. The almond fruit productivity via positive and negative shocks exposed an adverse relation to carbon dioxide emission. Grape fruit via positive shock shows a construct, but negative shock exposed an adverse association to carbon emission in Pakistan. Finally the guava fruit production exposed a construct linkage to CO2 emission via positive and negative shocks. Since agricultural activities and CO2 emissions are essential to resolving the pollution problem, a series of practicable steps must be taken by the Pakistani authorities to tackle this issue.

Spatial patterns of net greenhouse gas balance and intensity in Chinese orchard system.

Fruit production has been expanding due to the pursuit of healthier lifestyles in China. Determining the greenhouse gas (GHG) emissions status of the orchard system could contribute to adopting appropriate measures to alleviate climate change pressure from the growing fruit production. In this study, the net GHG balance and GHG intensity (GHGI) in the Chinese fruit production were estimated at the regional level using a meta-analysis based on databases compiled from relevant publications during 2000-2019, including soil nitrous oxide (N2O) and methane (CH4) emissions or uptake, upstream carbon dioxide (CO2) emissions related to farm practices, and the change of soil organic carbon (SOC) storage from the life cycle perspective. Results showed that the net GHG balance and GHGI varied among six regions, with ranges of 6.4 ± 0.3 to 10.0 ± 0.6 Mg CO2e ha-1 yr-1, and 2.2 ± 0.2 to 3.0 ± 0.2 kg CO2e kg-1, respectively. Synthetic nitrogen (N) fertilization was the largest source of overall GHG emissions from fruit production throughout China, accounting for 46% and ranging from 43% to 55% in the six fruit production regions. Fertilizer-induced N2O emissions were responsible for 22-31% of the total GHG emissions, and the N2O-N emission factor was identified as 0.7%. Also, power use for irrigation contributed a non-negligible 17% to the emissions on a national level, yet with large regional variations. In addition, fruit production in North, Northeast, Central, and East, and South China have relatively lower GHGIs than in Northwest and Southwest China. The estimated total GHG emissions from the Chinese fruit production were 102 Tg CO2e, with the contribution of SOC change to a decrease by 11% for the year 2018. Our results highlight an urgency to lower fruit production-related carbon emissions by extending optimized N fertilization and irrigation modes in China's orchard system.