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991.
Genetic Resources and Crop Evolution - The study involved evaluation of 96 wheat genotypes for early maturity and related traits and molecular characterization of trait specific candidate genotypes...  相似文献   
992.
Genetic Resources and Crop Evolution - Genetic diversity analysis contributes to the conservation, protection and utilization of genetic resources toward efficient management of germplasm. In this...  相似文献   
993.
Genetic Resources and Crop Evolution - During survey and study of local useful plants in the West Godavari district of Andhra Pradesh a less-known species, Arivela...  相似文献   
994.
Genetic Resources and Crop Evolution - Alliums comprise of popular spices and used for various culinary purposes and nutraceuticals. Poor genetic characterization and scarce information regarding...  相似文献   
995.
Landscape Ecology - Landscape connectivity, the extent to which a landscape facilitates the flow of ecological processes such as organism movement, has emerged as a central focus of landscape...  相似文献   
996.
European Journal of Plant Pathology - Symptoms of bunchy top, little leaf, leaf chlorosis with chlorotic streaks, leaf necrosis and stunted growth were noticed in two banana cultivars, Champa and...  相似文献   
997.
We analyzed data from a long-term rice–wheat cropping sequence to evaluate the effects of integrated nutrient management (INM) on yield trends and sustainability, nutrient balance and soil fertility of the system. After 30th cycle, grain yield of both the crops significantly declined under control and highest rice and wheat grain yields were obtained when 50% N supplied through green manure and farm yard manure, respectively. The magnitude of yield slope under INM was found considerably higher than 100% recommended fertilizer (RDF). Sustainable yield index (SYI) for both the crops were found lower in control but considerably higher with the 100% RDF and under INM. The soils under all the treatments suffered an apparent loss of K and N (except where organics replacing 50% N). Correlation study also reveals K is the sole factor for the yield sustainability as apparent K balance was negatively correlated with SYI and yield slope.  相似文献   
998.
Potassium (K) is one of the essential nutrients required by crops in large quantities; however, its use in agriculture by farmers is less than required in developing countries. This neglect has led to excess mining of K in soils by crop plants and has resulted in a negative balance of K in soils. This loss necessitates the need of more use of potassium fertilizers in agriculture. Rocks and minerals offer a potential fertilizer to utilize in agriculture as source of K. The crop trials revealed that feldspar, mica, glauconite, nepheline and shoenite are good sources of K for crops, especially in highly weathered acid soils. However, some researchers have reported no agronomic benefit of feldspar or granite rock application to crops. Overall the size modification, acidulation, microbial inoculants and preparation of K-enriched compost are the effective techniques to utilize K-bearing rocks and minerals. Very limited information is available on these aspects. Thus, in this review, an attempt has been to consolidate up-to-date information of indigenous rocks and minerals as possibilities for alternate sources of K for crop plants. Moreover, this area of research needs attention to utilize indigenous K sources, which can aid to limit the import and cost, of the establishment of potash fertilizer-based industries in developing countries.  相似文献   
999.
Water and temperature are critical for producing vegetable crops, especially during winter, when the availability of water is meager and temperature falls. Studies of drip irrigation and mulch were undertaken to find the effect on different growth and yield parameters in pepper (Capsicum annuum L.). The experiment was laid out in a split-plot design with four main and four subplots. Irrigation levels were placed on main plots and mulches on subplots with three replicates for each. All recorded vegetative parameters were higher with drip irrigation at 1.0 pan evaporation (Epan) and black polythene mulch. Physiological parameters such as photosynthesis rate (18.01 and 17.45 μmol m?2 s?1), transpiration rate (6.19 and 5.86 mmol H2O m?2 s?1) and chlorophyll content (27.34 and 28.39; 39.22 and 41.27 SPAD, respectively at 50 and 100 days after planting) were maximal in crops with drip irrigation at 1.0 Epan and mulched with black polythene. Soil and canopy temperature were significantly higher on flood irrigation at 1.0 Epan. Soil temperature was higher with the black polythene mulch, but canopy temperature was higher with no mulch. A higher level of drip irrigation and black polythene mulch result in early picking with higher yields compared with flood irrigation and no mulch.  相似文献   
1000.
ABSTRACT

Pedotransfer functions (PTFs) have been used to save time and cost in predicting certain soil properties, such as soil erodibility (K-factor). The main objectives of this study were to develop appropriate PTFs to predict the K-factor, and then compare new PTFs with Universal Soil Loss Equation (USLE) and the Revised Universal Soil Loss Equation (RUSLE) K-factor models. The K-factor was measured using 40 erosion plots under natural rainfall in Simakan Watershed, an area of 350 km2 in central of Iran. The Regression Tree (RT) and Multiple Linear Regression (MLR) were used to develop PTFs for predicting the K-factor. The result showed that the mean of measured K was 0.01 t h MJ?1 mm?1. The mean K value predicted by USLE and RUSLE was 2.08 and 2.84 times more than the measured K, respectively. Although calcium carbonate was not considered in the original USLE and RUSLE K-factors, it appeared in the advanced PTFs due to its strong positive significant impact on aggregate stability and soil infiltration rate, resulting in decreased K-factor. The results also showed that the RT with R2 = 0.84 had higher performance than developed MLR, USLE and RUSLE for the K estimation.  相似文献   
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