Productivity and profitability assessment of organically grown vegetables embedded in rice based cropping sequences in Sikkim Himalayas, North East India

Aim: The objective of the present study was to identify economically viable, profitable and resource efficient vegetables embedded rice-based cropping sequences under organic management for marginal and small farmers of Sikkim Himalayas, India.Methodology: Three-year fixed plot study was conducted to evaluate seven rice–based cropping sequences viz., rice–fallow (farmers’ practice), rice–fenugreek (leafy vegetable), rice–coriander (leaves), rice–radish, rice–broccoli, rice–potato and rice–vegetable pea were replicated four-times in a completely randomized block design. Results: Among the various rice – based cropping sequences, cultivation of rice–coriander (leaves) recorded higher production (67.3 kg ha-1 day-1), system productivity (24.6 t ha-1), relative economic efficiency (1040%) and net returns (376.1x103). However, rice-broccoli and rice–vegetable pea sequences recorded 8.6 and 4.4% higher B: C ratio, respectively, over the rice–coriander system. With regards to soil health, rice – vegetable pea cropping sequences resulted in maximum improvement in soil organic carbon (SOC) (1.26%), available soil N (415.2 kg ha-1), P (22.8 kg ha-1) and K (411.5 kg ha-1), soil microbial biomass carbon (SMBC) (344.7 µg MBC g-1 soil), dehydrogenase activity (DHA) (24.0 µg TPFg-1 soil h-1) and fluorescin di acetate (FDA) (38.8 µg FDAg-1 soil h-1) among the cropping sequences. Interpretation: Induction of vegetables in rice–fallow system under assured irrigation condition of Sikkim Himalayas, India not only enhances the farm productivity and profitability but also sustain the soil health on long term basis. Thus, rice-vegetable pea/coriander/broccoli based production systems under organic management hold great promises for sustaining livelihood of organic growers in Sikkim Himalayas over conventional rice– fallow system.

Fine root growth and soil nutrient dynamics during shifting cultivation in tropical semi-evergreen forests of northeast India

Aim: The present study aimed to understand the periodical changes in fine root biomass, production, turnover and carbon and nitrogen return in forest fallows following shifting agriculture in Mizoram, Northeast India. Methodology: Root biomass was determined using sequential coring method in different fallow lands (FL-3, FL-5 and FL-10) following shifting agriculture. Annual fine root production was calculated as the sum of differences between annual maximum and minimum root biomass of different diameter classes. Concentrations of carbon and nitrogen in soil and roots were determined using CHN auto-analyzer, and their accumulations and returns were computed as the product of mass and element concentrations. Results: Total root biomass was maximum (561 g m-2) at FL-10, which decreased to 141 g m-2 at FL-3 with greater accumulation of fine roots in upper soil layer (0-10 cm) and coarse roots in lower depths. Root biomass was maximum (1499 g m-2) at the time of slashing which decreased to about one fourth just after burning. The amount of organic matter, carbon and nitrogen return to soil through fine root death was significantly regulated by soil moisture, microbial biomass carbon and total nitrogen in different fallow lands. Interpretation: Addition of organic matter, carbon and nitrogen to soil through death and decomposition of fine roots is an important mechanism responsible for sustaining soil fertility and crop productivity in different fallow lands. The output of the study has implications for the management of fallow lands following shifting cultivation and modeling global cycles of carbon and nitrogen.

Barbecho como práctica cultural: una revisión histórica y alcances frente a la sostenibilidad / Fallow land as a cultural practice: a historical review and scope against sustainability

Introducción. El rápido aumento de la producción agrícola, las actividades extractivas y la expansión demográfica han originado degradación del suelo y la modificación del equilibrio dinámico propio de un ecosistema debido, entre otras cosas, a un cambio drástico en las formas tradicionales de agricultura como la disminución de periodos de descanso entre cultivos o barbecheo. Objetivo. Describir la dinámica de barbecho desde su origen, así como su influencia en el uso y transformación del suelo desde el punto de vista ambiental en un contexto histórico. Metodología. El método utilizado fue la consulta en bases de datos de revistas indizadas utilizando palabras claves como: barbecho, descanso, suelo, prácticas culturales andinas, prácticas agroculturales, agricultura tradicional y páramo; sin descartar artículos por fecha de publicación. Resultados. La evidencia encontrada en la literatura científica apunta que el barbecho es una práctica cultural tradicional que puede ser un modelo apropiado para el diseño de agroecosistemas, favoreciendo positivamente las condiciones ambientales y la sostenibilidad de ecosistemas estratégicos, como es el caso particular de los páramos cuya vocación primaria es la conservación.

Introduction: The rapid increase in agricultural production, extractive activities and demographic expansion have caused soil degradation and the modification of the dynamic equilibrium of an ecosystem due, among other things, to a drastic change in traditional forms of agriculture such as the decrease in rest periods between crop and fallow land. Objective: To describe the fallow land dynamics from its origin, as well as its influence on the use and transformation of the soil from the environmental point of view in a historical context. Methodology: The method used was the consultation in databases of indexed journals using keywords such as: fallow, rest, soil, Andean cultural practices, agricultural practices, traditional agriculture and paramo without discarding articles by publication date. Results: The evidence found in the scientific literature indicates that fallow is a traditional cultural practice that can be an appropriate model for the design of agroecosystems favoring positively environmental conditions and the sustainability of strategic ecosystems, as is the case of the paramos, whose primary vocation is conservation.

Sarcocystis spp. in red deer (Cervus elaphus), fallow deer (Dama dama), and pudu (Pudu pudu) in southern Chile / Sarcocystis spp. em veado (Cervus elaphus), Gamo (Dama dama) e Pudu (Pudu pudu) no sul do Chile

Worldwinde, cervids are considered an important source of infection and dissemination of a wide variety of pathogens, both for farm animals and humans. Among this diseases is sarcosporidiosis, which is a parasitic disease caused by Sarcocystis spp. (Protozoa: Apicomplexa). Most frequent clinical signs are hemolytic anemia, weakness, weight loss and decrease of growth and some species of Sarcocystis might cause abortions. The clinical disease in ruminants is fairly rare but the infection is very frequent. Infections are accumulative and the parasite does not generate immunity in any of the hosts. Ovine sarcosporidiosis is a serious issue in the some regions of Chile due to the macrocysts located in the muscle which means condemnation of the whole carcass. Sarcocystis spp. has been widely reported in red deer and other cervid species but in Chile the situation remains unknown. Nowadays there is little to no evidence of Sarcocystis in foreign deer in Chile and there is only one report of the parasite on pudu. The main goal of this study is to demonstrate the presence of Sarcocystis spp. in myocardium of red deer and fallow deer in Chile, and confirm the presence of Sarcocystis spp. in pudu. All cervid cases from 1994 to 2013 of the Institute of Animal Pathology of the Universidad Austral de Chile were reviewed. The animals selected were those in which a myocardium sample was taken. From the histopathological samples observed, it was found that 5 of the 9 red deer, 1 of the 4 fallow deer and in 11 of the 23 pudu there were Sarcocystis cysts in the myocardium. This study represents the first record for Chile of Sarcocystis spp. in myocardium of red deer and fallow deer. Stablishing the red deer, fallow deer and pudu as hosts of Sarcocystis aids to have a better understanding of the parasite epidemiology in Chile and the role of wild and captive cervids in the maintenance and spread of these parasites.(AU)

No mundo, os cervos são considerados uma fonte de infecção e propagação de uma grande variedade de patógenos para animais de criação e para os seres humanos. Entre estas doenças está a sarcosporidiosis, que é uma doença parasitária causada por Sarcocystis spp. (Protozoa: Apicomplexa). Os sinais clínicos mais comuns são anemia hemolítica, fraqueza, perda de peso e diminuição do crescimento e em algumas espécies de Sarcocystis podem causar abortos. A doença clínica em ruminantes é bastante rara, mas a infecção é muito comum. As infecções são cumulativos e o parasita não gera imunidade em nenhum dos seus hospedeiros. A Sarcosporidiosis ovina é um problema grave em algumas regiões do Chile devido a microcistos localizados no músculo provocando a reprovação total da carcaça. Sarcocystis spp. tem sido amplamente relatado em cervos vermelhos e outras espécies de cervídeos, mas no Chile a sua situação permanece desconhecida. Atualmente há pouca ou nenhuma evidência de Sarcocystis em cervos introduzidos no Chile e há apenas um relatório do parasita em pudú. O principal objetivo deste estudo é demonstrar a presença de Sarcocystis spp. no miocárdio no veado vermelho e cervo gamo no Chile e confirmar a presença de Sarcocystis spp. em pudus. Revisaram-se todos os casos de cervos desde 1994-2013 do Instituto de Patologia Animal da Universidad Austral de Chile. Os animais selecionados para o estudo foram aqueles em que se tomou amostra de miocárdio. Das amostras histopatológicas observadas, verificou-se que em cinco dos nove cervos vermelhos, em um dos quatro veados gamo e 11 dos 23 pudus tinham cistos de Sarcocystis no miocárdio. Este estudo representa o primeiro relatório para o Chile de Sarcocystis spp. no miocárdio de veados vermelhos e cervo gamo. Definir o veado vermelho, o cervo gamo e os pudú como anfitriões de Sarcocystis ajuda a uma melhor compreensão da epidemiologia deste parasita no Chile e o papel de cervos selvagens e em cativeiro para a manutenção e divulgação deste parasita.(AU)

Paratuberculosis: new histopathological findings in red deer (Cervus elaphus) and fallow deer (Dama dama) in Chile / Paratuberculosis: novos achados histopatológicos em Veado Vermelho (Cervus elaphus) e Gamo (Dama dama) no Chile

Paratuberculosis is a disease caused by Mycobacterium avium subsp. paratuberculosis (MAP) that affects domestic and wild ruminants. The most common gross lesions are emaciation and corrugation and thickening of the mucosa of the small intestine. Mesenteric lymph nodes might be enlarged. For the present study, 14 red deer and 9 fallow deer from game reserves or venison farms were analyzed. The lesions found correspond to those found by other authors in other geographic locations, except for some differences in histopathological examinations. Among these differences, stands out that intestinal lesions were concentrated mostly in the ileum and granulomas were shown to be more frequent in this section of the intestine than in the corresponding lymph node. Furthermore, in multibacillary lesions the inflammatory infiltrate in the lymph nodes was mainly composed of macrophages. These differences may be due to individual variations of the animals, the stage of disease or a different strain of the pathogen. This study allowed to obtain basic information about the disease and to describe patterns of lesions found in red deer and fallow deer with prediagnosis of clinical paratuberculosis which were not described in the literature before.(AU)

Paratuberculosis é uma doença causada por Mycobacterium avium subsp. paratuberculosis (MAP) que afecta ruminantes selvagens e domésticos. As lesões macroscópicas mais comuns são ondulação e espessamento da mucosa do intestino delgado. Os linfonodos mesentéricos podem aparecer com volume aumentado. Para este estudo, foram analisados 14 veados vermelhos e 9 veados gamo de reservas de caça e fazendas de carne. As lesões encontradas correspondem à encontrada por outros autores em outras localizações geográficas, com exceção de algumas diferenças no exame histopatológico. Entre essas diferenças, sobressai que as lesões intestinais se concentraram principalmente no íleo, os granulomas ocorreram com maior frequência nesta seção do intestino que no seu correspondente linfonodo. Além disso, nas lesões bacterianas, o infiltrado inflamatório linfonodos linfáticos era composta principalmente por macrófagos. Estas diferenças podem ser devidas a variações individuais dos animais, o estádio da doença ou de uma estirpe diferente do agente patogénico. Este estudo permitiu obter informação básica sobre a doença e descrever padrões de lesões encontradas em veados e em gamos com pré-diagnóstico, de paratuberculosis clínica nunca antes descritas na literatura.(AU)

Resposta do milho cultivado em sistema de plantio direto à aplicação de doses de nitrogênio e cultivo de plantas de cobertura em pré-safra / Response of corn grown in tillage system for the application of nitrogen doses in a sequence of plant cover

O uso de plantas de cobertura é capaz de produzir grandes quantidades de fitomassa, melhorando a ciclagem de nutrientes, em especial o nitrogênio, promovendo ganho de produtividade e economia de N-fertilizante. Diante disto, o objetivo foi avaliar o efeito do uso de doses de N-mineral associada às plantas de coberturas cultivadas na pré-safra no estado nutricional, acúmulo de nitrogênio e na produção de grãos da cultura do milho, em dois anos agrícolas. O experimento foi desenvolvido em um Latossolo Vermelho distrófico, com a cultura do milho em sistema de plantio direto. O delineamento experimental adotado foi em blocos ao acaso, em parcelas subdivididas, com quatro repetições. Os tratamentos principais foram: seis sistemas de semeadura (crotalária, feijão-de-porco, lablabe, milheto, mucuna-preta e pousio); nos tratamentos secundários: quatro doses de nitrogênio (0, 60, 120 e 180 kg ha-1 de N). A produção de grãos de milho não foi afetada pelo tipo de cobertura em pré-safra, independente da dose de nitrogênio aplicada no solo. Ainda, o uso de adubação nitrogenada no solo promove ganhos de produtividade de grãos de milhos, no primeiro ano de cultivo, independente do tipo de cobertura em pré-safra. No primeiro ano (2006/2007) as espécies de cobertura que produziram mais fitomassa foram mucuna-preta, feijão-de-porco, crotalárea-júncea e lablabe, enquanto que no segundo ano (2007/08) foram a crotalárea-júncea, milheto, lablabe, feijão-de-porco e mucuna-preta, respectivamente.

The use of cover crops can produce large amounts of biomass, improving the cycling of nutrients, particularly nitrogen, promoting productivity gains and cost savings. Given this, the objective was to evaluate the use of Nrates associated to cover crops grown in pre-harvest nutritional status, nitrogen accumulation and corn yield in both years. The experiment was conducted in an Oxisol with maize, no-tillage system. The experimental design was a randomized block, split plot with four replications. The main treatments were: six cropping systems (sun hemp, jack bean, lablab, millet, and velvet bean fallow) in secondary treatments: four doses of nitrogen (0, 60, 120 and 180 kg ha-1 N). Corn yield was not affected by the type of coverage for pre-season, regardless of the nitrogen applied in the soil. Still, the use of nitrogen fertilizer in the soil promotes gains in grain yield in the first year of cultivation, regardless of the type of coverage in pre-season. In the first year (2006/2007) the species of coverage produced more biomass were velvet bean, jack bean, sun hemp and lablab, while in the second year (2007/08) were the sun hemp, millet, lablab, jack bean and velvet bean, respectively.

Changes in Physical and Chemical Properties of Soil in Timber Sawmill Dumpsite in Abakaliki Abakaliki Southeastern, Nigeria. and Clima.

A study to assess changes in the physical and chemical properties of soil in timber saw mill dumpsite was carried out in Abakaliki between 2007 and 2008. Results showed that soil textural class remained sandy loamy. The lowest soil bulk density of 1.34 and 1.20 g cm-3 were obtained in the unburnt dumpsite in 2007 and 2008 resulting to 12% and 20% decline in 2007 and 2008 in the unburnt dumpsite relative to cropped land. The total porosity and gravimetric moisture content was a reverse of the soil bulk density. Higher total porosity and gravimetric moisture content were obtained in the unburnt and burnt dumpsites in that order relative to the fallow and cropped land. Infiltration rate followed the same trends as total porosity of the various sites. The lowest infiltration rate 15.02 and 35.82 mmhr-1 was observed in the cropped land. The soil pH decreased with depth in the dump and non-dumpsite but became strongly acid at 30 – 60 cm and 60 – 90 cm depths. The order of soil organic matter content was unburnt dumpsite > burnt dumpsite > fallow > cropped land. The available P and exchangeable K and Ca were highest in the burnt dumpsite. Heavy metals (Zn, Cu, Fe, and Pb) increased with time in the burnt and unburnt dumpsites but decreased in the cropped land. More concentration of heavy metals was observed in the 0 – 30 cm soil depth. The relative performance of maize grown on soils of the dump and non-dumpsites showed that there was better growth in the dump sites soils. However, the concentrations of heavy metals on tissue were found to be within normal range. Therefore, long term dumping of sawmill waste can influence soil properties and productivity.