Does Maturity Change the Chemical-Bromatological Makeup of Cladodes in Spineless Forage Cactus?

In Kutch (Gujarat District, India), there is a growing concern about the lack of good quality forage owing to the arid climate and poor soil health. Opuntia ficus-indica has been increasingly recognized as a drought-resilient forage in arid Kutch. This study seeks to identify the maturity phase of cactus cladodes with the best forage qualities. Five accessions of spineless forage cactus (CBG, No. 1270, No. 1271, No. 1308, and Bianca Macomer) and three cladode maturity phases (young, intermediate, and mature) were examined in a randomized block design experiment in a 5 _ 3 factorial arrangement. Although only mineral matter and total carbohydrate concentration were significantly different among the accessions, CBG showed better forage qualities than other accessions. Dry matter, organic matter, mineral matter, crude protein, ether extract, and total carbohydrate accumulations were higher in the intermediate phase. In the mature phase, relatively difficult to digest fiber components such as neutral detergent fiber, acid detergent fiber, lignin, cellulose, and hemicellulose increase. Our findings indicate that for spineless forage cactus grown in arid areas, the intermediate phase is the best phase to harvest cladodes for feeding livestoc

Conservation Agricultural Practices Impact on Soil Organic Carbon, Soil Aggregation and Greenhouse Gas Emission in a Vertisol

Conservation agriculture (CA), comprising of minimum soil disturbance and crop residue retention (>30%), with a diversified cropping system, has become increasingly popular around the world. It is recognized as a sustainable practice to improve soil health by augmenting key soil properties. However, scanty information exists about the effect of CA practices on soil organic carbon (SOC), aggregation and greenhouse gas emissions (GHG) in a vertisol. Thus, this study investigated the effect of CA practices on SOC, soil aggregation and GHG emission under soybean-wheat and maize-chickpea cropping systems in a vertisol in Central India. Treatment consisted of three different tillage practices, being conventional tillage (CT), reduced tillage (RT), and no tillage (NT) under four cropping systems viz., Soybean–Wheat, Soybean + Pigeon pea (2:1), Maize–Chickpea and Maize + Pigeon pea (1:1). Regardless of cropping system, the soil under NT and RT exhibited better aggregation (20.77 to 25.97% increase), and SOC (12.9 to 19.4% increase) compared to the CT practice in surface layers. The aggregate-associated C concentration increased with aggregate size, and it was highest with large macroaggregates and lowest with silt and clay fractions across different tillage and cropping systems. Higher SOC stock was recorded under NT (4.22 ± 0.133 Mg C/ha) compared to RT (3.84 ± 0.123 Mg C/ha) and CT (3.65 ± 0.04 Mg C/ha) practices at 0 to 5 cm depth. Thus, the adoption of CA practices reduced CO2 emissions, while also contributing to increases in SOC as well as improvement in soil structure

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Not AvailableIn recent years, conservation agriculture (CA) is increasingly being promoted among small-scale farmers in the tropics as well as subtropics. The myriad of research results generated from the adoption of CA ranges from significantly higher benefits than conventional farming to disappointing results. Although CA has been recommended by several researchers as a part of sustainable agriculture, there might be certain gaps and issues related to practicing CA in small-scale farms. Do the benefits from CA remain the same for small-scale farmers? How well does CA fit with agricultural, social, economic, and political contexts for small-scale farmers particularly in developing nations? One of the low adoption rates of CA in sub-Saharan Africa and South Asia is the lack of economic incentive and high machinery cost for small-scale farmers in which the process of conversion from conventional farming to CA is not profitable. There might be certain limitations in the potential for subsidizing farmers to adopt CA using payments for ecosystem services/carbon credit schemes. Therefore, the smallholding farmers with low risk-taking abilities are unsure of practicing CA in their farms despite proven economic benefits from CA in several parts of the world. In this regard, there is an urgent need to move ahead of the prescriptive approaches to provide sustainable soil and crop management options for small-scale farmers in the region. Therefore, this chapter will focus to answer the question: “Does CA work for small-scale farmers in developing countries?” or “Is it just the mindset of the people or the negative results of CA trials that led to low CA adoption in different parts of the world?”Not Availabl

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Not AvailableAggregation often provides physical protection and stabilisation of soil organic carbon (C). No tillage (NT) coupled with stubble retention (SR) and nitrogen (N) fertiliser application (90 N, 90 kg N ha−1 application) can help improve soil aggregation. However, information is lacking on the effect of long‐term NT, SR and N fertiliser (NT, SR + N) application on soil aggregation and C distribution in different aggregates in vertisols. We analysed the soil samples collected from 0‐ to 30‐cm depth from a long‐term (47 years) experiment for soil aggregation and aggregate‐associated C and N. This long‐term field experiment originally consisted of 12 treatments, having plot size of 61·9 × 6·4 m, and these plots were arranged in a randomised block design with four replications, covering an area of 1·9 ha. Soil organic C concentrations as well as stocks were significantly higher under the treatment of NT, SR + N only in 0–10 cm compared with other treatments such as conventional tillage, stubble burning + 0 N (no N application) and conventional tillage, SR + 0 N. Mineral‐associated organic C (MOC) of 0·053 mm) in the 0‐ to 30‐cm layer. We found that NT, SR + N treatment had a positive impact on soil aggregation, as measured by the mean weight diameter (MWD) through wet sieving procedure, but only in the top 0‐ to 10‐cm depth. MWD had significant positive correlation with water stable aggregates (r = 0·67, p 2 mm) had significantly higher organic C and N concentrations than small macroaggregates (0·25–2 mm) or microaggregates (0·053–0·25 mm). We also found that N application had a significant effect on MWD and soil organic C in vertisols. It is evident that better soil aggregation was recorded under NTSR90N could have a positive influence on soil C sequestration. Our results further highlight the importance of soil aggregation and aggregate‐associated C in relation to C sequestration. Copyright © 2016 John Wiley & Sons, LtdNot Availabl

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Not AvailableTo feed around 9.8 billion people by 2050, it is equally important to increase food production while maintaining the sustainability of the environment. Conservation agriculture (CA) is one of the approaches to manage agro-ecosystems in order to improve productivity, increase the profitability and food security and enhance the resource base and environment. Although many researchers have pointed out the prospects and concerns of adopting CA in different climatic conditions, CA in arid regions raises uncertainties due to its extreme climates, most of the soils with low water holding capacity, high potential evapotranspiration, low and non-uniform distribution of rainfall and greater wind erosion. However, CA practices could benefit the arid agriculture through moderation/reducing of evaporation, regulating water and nutrient in soil and reducing wind erosion. Arid soils, largely characterised by low soil organic carbon (SOC), have the greater potential for higher C sequestration with the use of CA practices. Among the key components of CA, no-tillage (NT) coupled with mulching might be effective in distribution of the soil moisture at proper stage of the crop growth. The emission of CO2 flux from soil and soil salinity are reduced with the adoption of CA in arid soils with the use of cover crops. Due to better aeration and nutrient movement in CA land, beneficial bacterial community and diversity are promoted. However, for CA to work effectively in arid regions, the three components of CA such as minimum disturbances of soil through no- and reduced-tillage, permanent soil cover and crop rotation must be critically followed together or simultaneously for improving soil health, crop productivity through high nutrient and water efficiency, carbon sequestration, mitigation of climate change and sustainability.Not Availabl

Repression of a matrix metalloprotease gene by E1A correlates with its ability to bind to cell type-specific transcription factor AP-2.

Adenovirus E1A 243-amino acid protein can repress a variety of enhancer -linked viral and cellular promoters. This repression is presumed to be mediated by its interaction with and sequestration of p3OO, a transcriptional coactivator. Type IV 72-kDa collagenase is one of the matrix metalloproteases that has been implicated in differentiation, development, angiogenesis, and tumor metastasis. We show here that the cell type-specific transcription factor AP-2 is an important transcription factor for the activation of the type IV 72-kDa collagenase promoter and that adenovirus E1A 243-amino acid protein represses this promoter by targeting AP-2. Glutathione S-transferase-affinity chromatography studies show that the E1A protein interacts with the DNA binding/dimerization region of AP-2 and that the N-terminal amino acids of E1A protein are required for this interaction. Further, E1A deletion mutants which do not bind to p3OO can repress this collagenase promoter as efficiently as the wildtype E1A protein. Because the AP-2 element is present in a variety of viral and cellular enhancers which are repressed by E1A, these studies suggest that E1A protein can repress cellular and viral promoter/enhancers by forming a complex with cellular transcription factors and that this repression mechanism may be independent of its interaction with p3OO

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Not AvailableConservation agriculture (CA) is considered a sustainable practice with the potential to maintain or increase crop productivity and improve environmental quality and ecosystem services. It typically improves soil quality and water conservation; however, its effect on crop productivity is highly variable and dependent on local conditions/management. Crop residue retention plays a crucial role in CA and can help to improve overall soil health and ultimately crop productivity and sustainability. However, weed control, herbicide resistance, and weed shift under residue retained fields is a major challenge. Moreover, CA can increase water infiltration and reduce soil loss and runoff. This reduces the surface transport of nitrate and phosphorus from agricultural fields and the eutrophication of water bodies, although leaching of nitrate to groundwater can potentially increase. In addition, CA has been proposed as one of the components in climate-smart agriculture, owing to its reduced period to seed/plant next crop, reduced soil disturbance and low consumption of fossil fuels. Therefore, compared to the conventional intensive tillage, CA has a greater potential for soil C sequestration, favors higher soil biodiversity, lowers greenhouse gas emission, and can assist in mitigating climate change. However, not all experiments report a positive impact. The understanding and decoding the site-specific complexities of CA system is important and requires a multidisciplinary approachNot Availabl

Soil Inorganic Carbon as a Potential Sink in Carbon Storage in Dryland Soils—A Review

Soil organic carbon (SOC) pool has been extensively studied in the carbon (C) cycling of terrestrial ecosystems. In dryland regions, however, soil inorganic carbon (SIC) has received increasing attention due to the high accumulation of SIC in arid soils contributed by its high temperature, low soil moisture, less vegetation, high salinity, and poor microbial activities. SIC storage in dryland soils is a complex process comprising multiple interactions of several factors such as climate, land use types, farm management practices, irrigation, inherent soil properties, soil biotic factors, etc. In addition, soil C studies in deeper layers of drylands have opened-up several study aspects on SIC storage. This review explains the mechanisms of SIC formation in dryland soils and critically discusses the SIC content in arid and semi-arid soils as compared to SOC. It also addresses the complex relationship between SIC and SOC in dryland soils. This review gives an overview of how climate change and anthropogenic management of soil might affect the SIC storage in dryland soils. Dryland soils could be an efficient sink in C sequestration through the formation of secondary carbonates. The review highlights the importance of an in-depth understanding of the C cycle in arid soils and emphasizes that SIC dynamics must be looked into broader perspective vis-à-vis C sequestration and climate change mitigation