10 research outputs found
Not Available
Not AvailableThe transplanted puddled rice (TPR) is a water, labour and energy intensive practice, and also emits vast amount of green-house gasses (GHG), particularly methane. The water guzzling nature of TPR and escalating labour prices drives towards the search for alternative methods of rice production. Among different methods of rice cultivation, direct-seeded rice (DSR) received much attention in this way; however, major constraints in DSR are identified as poor crop establishment, weed infestation, nematode occurrence and imbalanced nutrient and faulty water management practices. This paper summarises the improved production technologies for DSR viz. precision levelling, early-maturing varieties, seed priming, effective water, nutrient and weed management. It is evident from the review that grain yield, water productivity and net income could be enhanced by laser land levelling as compared to traditional levelling. Alternate wetting and drying method of irrigation in DSR resulted in less water requirement without any yield penalty. Application of Pendimethalin @1 kg a.i. /ha as pre-emergence followed by post-emergence application of bispyribac sodium @ 25g a.i./ha recorded higher grain yield and better weed control efficiency. Use of Trichoderma viride@ 2.5 kg/ha was found effective to control nematode infestation in DSR. Moreover, compared to TPR, DSR had less methane emission and global warming potential. Thus, DSR is a feasible alternative to TPR with a good potential to save water, reduce labour requirement, and to mitigate the climatic risks in Indian agriculture.Not Availabl
Not Available
Not AvailableInclusion of legumes in the cropping system has been known since times immemorial. Legume is a natural mini-nitrogen manufacturing factory in the field and the farmers by growing these crops can play a vital role in increasing indigenous nitrogen production. Legume help in solubilizing insoluble P in soil, improving the soil physical environment, increasing soil microbial activity, and restoring organic matter, and also has smothering effect on weed. The carryover of N derived from legume grown, either in crop sequence or in intercropping system for succeeding crops, is also important. In a country like India, where the average consumption of plant nutrients from chemical fertilizers on national basis is very low, the scope for exploiting direct and residual fertility due to legumes has obviously a great potential. This article deals with the beneficial effect of important legumes on increasing productivity and nutrient use-efficiency in various systems. Sorghum, pearl millet, maize, and castor are mainstay in dry lands and marginal and sub-marginal lands. Sorghum yield increased when sown after cowpea, green gram, and groundnut. Grain legumes like groundnut or cowpea provide an equivalent to 60 kg N ha on the subsequent crop of pearl millet. Various studies have shown that among legume/cereal intercropping system, the combination of maize/pigeon pea is considered to be highly suitable with a minimum competition for nutrients, while legume/legume intercropping system, pigeon pea/groundnut system is the most efficient one in terms of resource use-efficiency. In alley cropping system, Leucaena leucocephala (Subabul) prunings provide N to the extent of 75 kg, which benefits the intercrop castor and sorghum. Nitrogen economy through intercropped legume is still a researchable issue because the key point for leguminous crop grown in intercropping system is the problem of nodulation. Incorporation of whole plant of summer green gram/black gram into soil (after picking pods) before transplanting rice resulted in the economizing (40–60 kg N ha−1, 30 kg P2O5, and 15 kg K2O per ha) of rice in rice-wheat system. Similarly, 6–8 weeks old green manure crop of sunhemp or dhaincha accumulates about 3–4 t ha−1 dry matter and 100–120 kg N ha−1 which, when incorporated in situ, supplements up to 50% of the total N requirement of rice. Legumes with indeterminate growth are more efficient in N2 fixation than determinate types. Fodder legumes in general are more potent in increasing the productivity of succeeding cereals. The carryover of N for succeeding crops may be 60–120 kg in berseem, 75 kg in Indian clover, 75 kg in cluster bean, 35–60 kg in fodder cowpea, 68 kg in chickpea, 55 kg in black gram, 54–58 kg in groundnut, 50–51 kg in soybean, 50 kg in Lathyrus, and 36–42 kg per ha in pigeon pea. Direct and residual effect of partially acidulated material and mixture of rock phosphate + single superphosphate were observed to be better when these were applied to green gram in winter season than to rice in rainy season simply because of legume effectNot Availabl
A distinctive adnexal (usually paratubal) neoplasm often associated with peutz-jeghers syndrome and characterized by STK11 alterations (STK11 adnexal tumor): a report of 22 cases.
We describe 22 examples of a novel, usually paratubal, adnexal tumor associated with Peutz-Jeghers syndrome in nearly 50% of cases that harbored STK11 alterations in all tested (n=21). The patients ranged from 17 to 66 years (median=39 y) and the tumors from 4.5 to 25.5 cm (median=11 cm). Most (n=18) were paratubal, with metastases noted in 11/22 (50%) and recurrences in 12/15 (80%). Morphologically, they were characterized by interanastomosing cords and trabeculae of predominantly epithelioid cells, set in a variably prominent myxoid to focally edematous stroma, that often merged to form tubular, cystic, cribriform, and microacinar formations, reminiscent of salivary gland-type tumors. The tumor cells were uniformly atypical, often with prominent nucleoli and a variable mitotic index (median=9/10 HPFs). The tumors were usually positive to a variable extent for epithelial (CAM5.2, AE1/AE3, cytokeratin 7), sex cord (calretinin, inhibin, WT1), and mesothelial (calretinin, D2-40) markers, as well as hormone receptors. PAX8, SF1, and GATA-3 were rarely positive, while claudin-4, FOXL2, and TTF-1 were consistently negative. All sequenced tumors (n=21) harbored alterations in STK11, often with a loss of heterozygosity event. There were no other recurrently mutated genes. Recurrent copy number alterations included loss of 1p and 11q, and gain of 1q, 15q, and 15p. Despite an extensive morphologic, immunohistochemical, and molecular evaluation, we are unable to determine with certainty the histogenesis of this unique tumor. Wolffian, sex cord stromal, epithelial, and mesothelial origins were considered. We propose the term STK11 adnexal tumor to describe this novel entity and emphasize the importance of genetic counseling in these patients as a significant number of neoplasms occur in association with Peutz-Jeghers syndrome