ABSTRACT
The biotechnological interest in genus Physalis has increased in the last decades, however, there are still few micropropagation studies of this genus. The objective of this study was to evaluate P. angulata photoautotrophic and photomixotrophic micropropagation with gas exchange under seven light spectra and five concentrations of sucrose. Lighting were yellow, blue, white, red, green, red + blue LEDs and natural light filtered by mesh. Sucrose concentrations were 0, 7.5, 15, 22.5 and 30 g.L-1. Phytotechnical, anatomical features and photopigment contents were evaluated through stem and root segment length, leaf number, leaf area, chlorophyll a and b contents, carotenoids, adaxial epidermis, palisadic and spongy parenchyma and abaxial epidermis. The data were compared by Scott-Knott's mean test and principal components analysis using the R software. Comparing the variables within lighting types, it was observed that only the screen treatment, screen-filtered natural illumination, obtained assessment in all variables. Comparing the levels of sucrose, it was observed that the treatment 15 g.L-1 sucrose obtained the highest number of averages with maximum evaluation. It was concluded that the natural light filtered by screen with 50% of shading allowed the photoautotrophic micropropagation of P. angulata. Better development results were observed in photomixotrophic micropropagation with 15 g.L-1 of sucrose.
O interesse biotecnológico em Physalis aumentou nas últimas décadas, porém, ainda existem poucos trabalhos de micropropagação desse gênero. Objetivou-se avaliar sua micropropagação fotoautotrófica e fotomixotrófica com troca gasosa sob sete tipos de iluminação e cinco concentrações de sacarose. Foram utilizados LEDs amarelo, azul, branco, vermelho, verde, vermelho + azul e luz natural filtrada por malha. As concentrações de sacarose foram 0, 7,5, 15, 22,5 e 30 g.L-1. Características fitotécnicas, anatômicas e teor de fotopigmentos foram avaliados através de comprimento de segmento de caule e raíz, número de folhas, área foliar, teores de clorofilas a e b, carotenoides, epiderme adaxial, parênquimas paliçádico e esponjoso e epiderme abaxial. Os dados foram comparados por teste de média Scott-Knott e análise de componentes principais utilizando-se o software R. Comparando-se as variáveis dentro de tipos de iluminação, observou-se que apenas o tratamento screen, iluminação natural filtrada por malha, obteve avaliação máxima em todas as variáveis. Comparando-se os níveis de sucrose, observou-se que o tratamento 15 g.L-1 sacarose obteve o maior número de médias com avaliação máxima. Concluiu-se que a luz natural filtrada por tela com 50% de sombreamento permitiu a micropropagação fotoautotrófica de P. angulata. Observou-se melhores resultados de desenvolvimento na micropropagação fotomixotrófica com 15 g.L-1 de sacarose.
Subject(s)
Botany , Physalis , Tissue Culture TechniquesABSTRACT
ABSTRACT@#Colletotrichum is one of the most significant and common plant pathogens, infecting many economically important crops worldwide. Colletotrichum is also one of the most studied fungal genera in Malaysia because it contains many species that infect various types of agricultural crop including fruit, vegetable and industrial crops. Studies on Colletotrichum spp. are mostly focused on the causal pathogens, the host range and disease management. Among the host crops, most studies on Colletotrichum spp. have been conducted on infection in chilli (Capsicum spp.), which, in Malaysia, first arose in the 1980s and still continues to be a problem to this day. Studies have also been conducted on Colletotrichum spp. associated with anthracnose in fruit crops including dragon fruit, papaya, banana and mango. Disease management of anthracnose pathogens postharvest has also been conducted to prolong the shelf life of these fruit crops. In this review, Colletotrichum spp. associated with chilli and several fruit crops as well as their disease management are highlighted. There have been many changes in Colletotrichum taxonomy and systematics in recent years, affecting the identification of anthracnose pathogens reported in Malaysia. Colletotrichum species identified solely by morphology or solely via the internal transcribed spacer (ITS) region should be referred to as sensu lato (in the broad sense) since many species belong to species complexes. Species within a species complex are closely related, and most are cryptic species particularly species in the C. gloeosporioides and C. acutatum complexes which are commonly associated with agricultural crops in Malaysia. Due to the importance of Colletotrichum spp. as plant pathogens, up-to-date identification methods should be used since accurate species identification of Colletotrichum is crucial for formulating suitable disease management programmes as well as for plant quarantine and biosecurity purposes. This review provides the current knowledge on the status of Colletotrichum spp. associated with agricultural crops in Malaysia and potential control methods on different types of agricultural crops.
ABSTRACT
Abstract This research evaluated the monthly variation of plant mineral nutrition in six species of fruit trees over a year. Leaf samples were taken from the fruit trees and nutritional status (N, P, K, Ca, Mg, Fe, Zn, Cu, Mn, and Mo) was determined in the leaves in a month basis from April until November for apple, persimmon and peach. Mandarin mineral nutrition was monitored for one year, and grape and fig from May to November. Using this data, the Diagnosis Recommendation Integrated System (DRIS) was also calculated to evaluate the nutrient balance in the plants. The concentration of N and P had seasonal differences, especially in apple and peach, which reached the peak during the summer. Apple, fig, and grape trees had large ranging on their mineral contents over the year, especially with the P and K levels reaching the minimum during the harvesting season. However, the seasonal changes in leaf micronutrient concentrations were not uniform and not affected by phenological stage. The DRIS data demonstrated that mandarin had the best nutrient balance compared to others and that K was the most limiting element among the fruit trees. In summary, the current data suggest the occurrence of a significant seasonality in mineral nutrition in these six fruit trees, especially in temperate ones.