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To meet the requirement of increasing demand for food and fodder and to ensure food security, it is important to increase the production potential through soil health improvement in rainfed agroecological regions besides the irrigated regions. Degrading soil health because of decrease in soil organic carbon (SOC) and resultant decline in overall soil fertility in rainfed areas is a major threat to sustenance of crop and fodder productivity. In view of the importance of soil organic matter (SOM), and its close relationship with soil health and crop production, its role in carbon sequestration and nutrient cycling has gained much attention in the last few years. Restoration of SOM contents in the soil to optimal levels will not only improve the soil health of rainfed agroecosystem, but will also significantly contribute towards boosting crop production. In this article, we have critically reviewed the impacts of different crop management practices on SOC content and its impact on soil health and crop productivity in rainfed agroecological regions of the country. [ABSTRACT FROM AUTHOR]

This article summarizes the utility of farm pond technology as an adaptation strategy to overcome water shortage due to several reasons, including climate change. This technology has the potential to increase availability of water for supplemental irrigation, increase in cropped area and productivity leading to increase in net returns from crops. Farm pond offers a solution to overcome the increased frequencies of drought, particularly mid-season and terminal drought under climate change scenario. The article advocates for policy intervention to promote one pond for each farm holding having an area of 2.0 ha at individual farm level or on community-sharing basis. Constraints for large-scale implementation of farm pond technology are also discussed. [ABSTRACT FROM AUTHOR]

Maintenance of soil physical health at its optimum level is essential for sustainable crop production and rational use of natural resources without jeopardizing their quality. The ongoing conventional tillage practices for crop production using intensive ploughing and removal of crop residue from the field have resulted in an increase in surface crusting, soil compaction, soil erosion, decrease in water infiltration and ultimately aggravation of the overall soil physical health deterioration. In recent years, many agricultural scientists across the world have recommended conservation agriculture as a solution to overcome the adverse effects of conventional tillage practices on soil physical health. Conservation agriculture is mainly an integration of three crop management practices, viz. minimum or no-tillage, permanent retention of crop residue and crop rotation. The present data indicates that conservation agriculture can improve soil physical properties and associated processes especially, soil water infiltration and storage, soil aeration, soil structure and soil porosity. It reduces soil erosion, soil compaction and crusting, and optimizes the soil temperatures for successful crop production. This article reviews the role of conservation agriculture in improving soil physical health and its associated processes. [ABSTRACT FROM AUTHOR]

The present study was conducted in 2009-10 with the objective to monitor the effect of restorative soil management practices on biological soil quality. The experiment was initiated in 1995 in a strip-split-split plot design with three replications. Sorghum and castor were grown in two-year rotations. The procedure comprised of two tillage treatments: conventional tillage (CT) and minimum tillage (MT; main plots), three residues treatments: sorghum stover (SS), Gliricidia loppings (GL), no residue (NR; sub-plots), and two nitrogen levels 0 (N0) and 90 kg ha-1 (N90) (sub-subplots). After 15th year of the experiment, activities of the soil enzymes, microbial biomass carbon (MBC), labile carbon (LC) and organic carbon (OC) were studied. Soil management treatments significantly influenced the soil enzyme activities. Enzyme activity was significantly correlated with MBC, LC and OC. The biological soil quality has been assessed in terms of GMeanBSQI (geometric mean of biological soil quality index). From the viewpoint of GMeanBSQI, the order of superiority of soil management treatments was: MT (0.82) > CT (0.69). The performance of the residues was in the order GL (0.87) > SS (0.75) > NR (0.65). Nitrogen @ 90 kg ha-1 (0.81) proved superior to no nitrogen (N0 - 0.70). Among all the treatment combinations, MTGLN90 was found to be the most superior management option for ensuring higher GMean in rainfed Alfisol soils. The present study indicates that crop residue management under minimum tillage is of great significance in improving the biological soil quality indicators and indices. The results obtained are significant in improving biological soil quality index and crop productivity through appropriate soil management. [ABSTRACT FROM AUTHOR]

A new disease in Jatropha curcas L. plants was observed during the summer season in 2009 and 2010 in plantations in several Indian states, including Andhra Pradesh, Assam, Chhattisgarh and Madhya Pradesh. The outbreak of the disease coincided with the leafdropping (dormant) stage of the crop, which sets in with the increasing moisture stress. Affected J. curcas plants showed drying along with shrivelling, and discoloration of the stem with sticky reddish-brown exudation at the base of the plants. Black lesions (soft and rotting) on the stem under the bark and cambium layer were also observed. From the affected stem parts, fungal cultures were isolated and tested for their pathogenicity on pot-grown plants. The fungal isolates caused symptoms on J. curcas leaves and petioles (black spots, 1-3 mm in diameter). Then they spread to the stems causing shrivelling and gummosis of hard-wood stems, and finally led to the death of the infected plant. The causal fungus was identified as Botryosphaeria dothidea using microscopic observations of hyphae and spores, and internally transcribed spacers (ITS) sequencing technique. In addition, four other fungal isolates were also isolated from the affected tissues, which were identified as Macrophomina phaceolina, Phomosis longicolla, Fusarium oxysporum and Alternaria alternata using the ITS sequencing technique. The role of these fungal cultures, i.e. whether they grow as saprophytes on the affected dead tissues or have any role in causing the black rot disease, needs further study. Spraying J. curcas plants showing early symptoms of this disease with Bavistin (carbendazim 50% WP) at the rate of 2 g l-1 water controlled the spread of the symptoms and led to the recovery of plants with new leaf growth after the rains. [ABSTRACT FROM AUTHOR]

Increasing concentration of greenhouse gases in the atmosphere and the adverse effects associated with climate change have necessitated the need for identification of systems with high carbon sink as a mitigation strategy. Tree-based systems with short rotation species either as farm forestry or agroforestry systems have the potential to sequester carbon in a short period. Leucaena and eucalyptus-based systems, mostly planted at closer spacing, are widely distributed in several districts of Andhra Pradesh, India. The objective of this communication is to analyse the carbon storage of two land-use systems (farm forestry and agroforestry) with two short rotation tree species, viz. leucaena and eucalyptus, and to evaluate their carbon sequestration potential in degraded lands. Trees in farm forestry systems were close planted at 1 × 1 m and 3 × 2 m, whereas those in agroforestry systems were planted at wider spacing of 3 × 0.75 m and 7 × 1.5 m in paired rows, in leucaena and eucalyptus respectively. The carbon stock of leucaena farm forestry system was 62 Mg/ha, whereas in eucalyptus farm forestry system, it was 34 Mg/ha for a rotation of 4 years. Biomass and carbon accumulation were relatively higher in farm forestry systems and the rate of accumulation was highest during the third year. It is concluded that, leucaena and eucalyptus systems can play an important role as carbon sinks and contribute significantly to the removal of CO2 from the atmosphere. [ABSTRACT FROM AUTHOR]

Soil physical degradation has become a serious problem in both rainfed and irrigated areas of India. According to an estimate, about 90 m ha area is experiencing soil physical constraint in the country. In rainfed regions, among several other constraints related to crop and climate, soil physical constraints are the key which severely limit crop productivity. The predominant soil constraints which are governed by the principles of soil physics include subsurface hard pan and compactness, crusting and hardening, slow and high permeability, non-optimal porosity, poor soil structure, poor water receptivity, retention and transmission, etc. It is now well-established that unless the soil physical environment is maintained at its optimum level, the genetic yield potential of a crop cannot be realized even when all the other requirements are fulfiled. The optimum soil physical environment creates a suitable condition for better crop production both in irrigated and rainfed regions. Rainfed agriculture, often referred to as dryland agriculture, is practiced in areas that are relatively warmer (arid, semi-arid) and dry sub-humid regions of the country. These regions are highly diverse, ranging from resource-rich areas with good agricultural potential to resource-constrained areas with a much more restricted potential. These regions represent a wide variety of soil types, agro-climatic and rainfall conditions. This article discusses the soil physical constraints in rainfed regions of India. [ABSTRACT FROM AUTHOR]

Subsistence agriculture practice and a combination of harsh climate and fragile soils along with increasing demographic pressure are matters of great concern from the viewpoint of resource management and longterm sustainability in the semi-arid tropical Alfisol soils of India. In this study, soil quality index (SQI) has been computed on 190 sites of farmers' fields in southern India to evaluate the possible effect of land management practices on soil degradation and determine the critical levels of soil organic C stock to maintain a desirable SQI and also suggest appropriate management practices. In all, 26 predominant physical, chemical and biological properties of soils were studied and based on principal component analysis, moisture retention at field capacity, available soil N, available P, DTPA-extractable Zn, exchangeable sodium percentage, C-mineralization and bulk density were identified as the key indicators of the study region. SQI was also computed using four soil functions, viz. nutrient cycling, availability of water, resistance of soil to degradation, and salinity and sodicity. Soil resilience index was computed using data on substrateinduced respiration after exposing the soil to heat stress. SQI was highest under paddy followed by permanent fallow, maize, cotton, intercropping, redgram, and was lowest under castor system. Based on the results, it was observed that the soils which had higher SQI were also productive and they exhibited higher resilience capacity. An amount of 8.6 Mg ha-1 soil organic C stock per 15 cm depth was found essential to maintain soil quality and 2.2 Mg ha-1 of organic matter was needed every year to maintain this stock. On-farm participatory research trial was conducted using SQI as a tool for sustainable land-management practices. [ABSTRACT FROM AUTHOR]

This article examines the potential of conservation agriculture (CA) in rainfed areas particularly in the arid and semi-arid regions of the Indian subcontinent. The CA practices under different types of rainfall, soil and production system were identified based on the analysis of studies undertaken in different agro-climatic regions of India. The net benefits from different suggested CA practices were estimated at current prices for the year 2010 based on the results of long-term experiments conducted at the Central Research Institute for Dryland Agriculture, Hyderabad, India and centres of its All-India Coordinated Research Project on Dryland Agriculture, which ranged from Rs 325 to 18,000 ha-1. The capital requirement of various CA practices was also estimated. The analysis shows that CA in its broader context not only improves soil health but also gives higher net returns per unit of land to the farmers. However, the CA practices need to be adopted selectively in different rainfall, soils and agro-ecological situations. The advantage of CA practices can be availed in rainfed agro-ecology, if practised appropriately over long-term basis. Higher carbon sequestration through CA practices may also give additional benefits in terms of carbon emission reduction, if made easily tradable in future. However, for promotion of CA practices across diverse agroecologies, appropriate policy, and institutional and technology support would be a prerequisite. [ABSTRACT FROM AUTHOR]

The article focuses on a study on micro-level agromet advisory services using block level weather forecast. It states that Agromet Advisory Service (AAS) deals with extension agrometeorology, and mentions that Central Research Institute for Dryland Agriculture has introduced a research programm of the Indian Council of Agricultural Research to enhance resilience of Indian agriculture to climate change.