Changes in soil organic carbon, dehydrogenase activity, nutrient availability and leaf nutrient concentrations in a mango orchard soil was evaluated from four years (2007)(2008)(2009)(2010)(2011) field experiment on a Typic Ustocrepts soil of subtropical region in Lucknow, India. Organic (FYM, vermicompost, mulching, Azotobacter, PSM and Trichoderma harzianum) and inorganic (N, P, K) substrates were applied each year within the tree basin. It was observed that soil and leaf nutrients concentrations significantly increased in organic and inorganic amended soils as compared to control. Vermicompost, organic mulching and microbial inoculation significantly enhanced soil organic carbon content, available nutrients, dehydrogenase activity and leaf nutrient concentrations. Dehydrogenase activity was highest (1.85 µg TPF g -1 h -1 ) in organically treated soils. Surface soil (0-10 cm depth) showed higher dehydrogenase activity (1.29 to 1.85 µg TPF g -1 h -1 ) as compared to lower soil depths in all the treatments.

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The goal of this study was to assess the influence of different organic fertilisers -vermicompost, mulching, Azotobacter, phosphate solubilising microbes (PSM) and Trichoderma harzianum added each year to mineral fertilisers containing NPK and to farmyard manure (FYM) on leaf nutrient status, tree growth, fruit yield and quality of guava grown in low fertile soil. The results revealed that vermicompost, bio-fertilisers and organic mulching resulted in yield and fruit quality boosters, as compared to application of NPK and FYM as the only organic fertiliser. Significant differences in plant height, canopy spread and stem girth of guava plants were obtained in combination, where Azotobacter, T. harzianum, PSM and organic mulching were applied. The leaf nutrient contents (N, P, K, Ca, Mg, Fe, Cu, Mn and Zn) were within sufficient ranges. Fruit yields and quality were highest in combination, where vermicompost, Azotobacter, T. harzianum, PSM and organic mulching was applied. Fruit quality parameters viz. soluble solid concentration, titratable acidity, total sugars and ascorbic acid showed positive correlation with the available macro-and micronutrients in the soil.

Farmers have no alternative but to adopt high-density planting for enhancing fruit productivity level and profitability with the shrinking land resources and smaller land holding sizes. The highest yield of 16 t ha -1 followed by 10.0 t ha -1 and the least of 5.5 t ha -1 was recorded from 400, 267 and 100 trees ha -1 , respectively from 19 yrs old Dashehari mango orchard in sandy loam soils at research farm of ICAR-CISH, Rehmankhera, Lucknow. Planting density systems (1600, 800, 400, 266, 178 and 100 trees ha -1 ) also impacted soil properties. Water holding capacity varied between 16.6 to 26.1 % across systems while porosity ranged from 46.2-71.5 %. Likewise, bulk density and particle density had values of 1.2 to1.7 and 2.2 to 2.9 g cm -3 respectively. The mean soil organic carbon content was 0.38%, pH of 7.2, available N, P, K was 66.92, 13.91 and 77.85 mg kg -1 respectively. Soil and leaf micronutrients analyzed across six different density systems showed wide variations and indicated the need for optimum nutrient management. Significant and positive correlations were recorded between soil organic carbon with other soil properties. The study revealed that medium density system (400 trees ha -1 ) is to be practiced at farmers' field.

Pepino (Solanum muricatum) is an Andean region's crop, originated from South America. The crop has medicinal values and underutilized for its cultivation. It has a wider adaptability across the different locations of Spain, New Zealand, Turkey, Israel, USA, Japan etc. The crop can be grown under diverse soil and climatic conditions in India also. Its fruits are juicy, mild-sweet, sub-acidic and aromatic berry which are rich in antiglycative, antioxidant, dietary fibres and low calorific energy. Fruit is visually attractive with golden yellow colour with purple stripes. The crop was evaluated for its growth and development at ICAR-Central Institute for Subtropical Horticulture, Rehmankhera, Lucknow, Uttar Pradesh, India (planted in the month of October, 2014). The results of the study exhibited its adaptation to climatic conditions of subtropics with higher yield and acceptable fruit quality.

Evaluation of the thermal heat requirement of Brassica spp. across agro-ecological regions is required in order to understand the further effects of climate change. Spatio-temporal changes in hydrothermal regimes are likely to affect the physiological growth pattern of the crop, which in turn will affect economic yields and crop quality. Such information is helpful in developing crop simulation models to describe the differential thermal regimes that prevail at different phenophases of the crop. Thus, the current lack of quantitative information on the thermal heat requirement of Brassica crops under debranched microenvironments prompted the present study, which set out to examine the response of biophysical parameters [leaf area index (LAI), dry biomass production, seed yield and oil content] to modified microenvironments. Following 2 years of field experiments on Typic Ustocrepts soils under semi-arid climatic conditions, it was concluded that the Brassica crop is significantly responsive to microenvironment modification. A highly significant and curvilinear relationship was observed between LAI and dry biomass production with accumulated heat units, with thermal accumulation explaining >or=80% of the variation in LAI and dry biomass production. It was further observed that the economic seed yield and oil content, which are a function of the prevailing weather conditions, were significantly responsive to the heat units accumulated from sowing to 50% physiological maturity. Linear regression analysis showed that growing degree days (GDD) could indicate 60-70% variation in seed yield and oil content, probably because of the significant response to differential thermal microenvironments. The present study illustrates the statistically strong and significant response of biophysical parameters of Brassica spp. to microenvironment modification in semi-arid regions of northern India.

Incidence and severity of mango anthracnose was studied during 2013, 2014 and 2015 for its relation with weather parameters. Twenty two mango orchards of cv. Dashehari, aged between 20-35 years in Lucknow district of Uttar Pradesh were selected for this study. The statistical analysis at different locations indicated highest incidence of 40.0, 29.2 and 29.6 per cent in three years respectively. Differences in disease severity were also observed among the years and within the orchards. Cooler months had high humid thermal ratio (HTR) values and warmer months mostly had low (1.2 to 3.5) HTR values. Significant positive correlation was found between HTR and anthracnose incidence and severity. The study inferred that humid thermal ratio may be used for prediction of the disease as a ratio of agroadvisory services to recommend timely protection measures to the farmers.

Field experiments were carried out at IARI research farm, New Delhi representing semi-arid climatic condition, to evaluate the growth and yield of oilseed Brassica using thermal indices. Two cultivars of Brassica juncea viz., Pusa Jaikisan and Varuna, widely grown in north and north-western parts of the country, were sown on ten different dates from 1st October to 3rd December at weekly interval. Three widely used thermal indices viz, growing degree days (GDD), heliothermal units (HTU) and photothermal units (PTU) were computed up to maximum biomass production in both the seasons. It was observed that GDD was able to explain variation in biomass, seed yield and oil content to the tune of 75, 66 and 78 per cent while PTU could explain 73, 66 and 77 per cent variations respectively. The yields and oil content of these two cultivars were highly influenced by the differential thermal environment and delay of sowing; decreased seed yield and oil content significantly.