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Background: Livestock productivity and health are adversely affected by heat stress (HS). The aim of this study was to determine the effects of HS on the thermoregulation and hormonal profile in Assam Hill Goats reared in the subtropical hilly regions of Meghalaya so as to arrive at a conclusion on its heat adaptation abilities. Methods: An experiment was conducted during the year 2022 for 120 days with twelve (12) Assam Hill Goats, aged between 3-5 months, randomly divided into 2 groups (n= 6 per group). The goats in group I were exposed to HS through natural exposure to sunlight during the extreme summer months (May to August) for 07 hours (8 AM to 3 PM) during grazing. The control animals (CON, group II) were maintained under shade with no exposure to sunlight. Thermoregulatory responses viz., rectal temperature, respiratory rate and pulse rate and body weight data were recorded every 15 days interval of the sampling period. The hormonal profile viz., serum T3 (nmol/L), T4 (nmol/L) and Cortisol (ng/mL) were also determined. Result: Results revealed a significant (p<0.05) increase in rectal temperature, pulse rate (day 45 onwards to day 120) and respiratory rate in HS group in comparison to CON. A significantly (p<0.05) lower average daily gain was recorded in HS group. Serum T3 and T4 concentrations were significantly (p<0.05) reduced and cortisol concentration was significantly (p<0.05) elevated in HS group in comparison to CON. In conclusion, Assam Hill Goats exposed to environmental HS shows elevated thermoregulatory responses, decreased thyroid hormone activity and increased cortisol activity to reduce production to support life sustaining activities in the hilly regions. [ABSTRACT FROM AUTHOR]

Performance of 27 improved groundnut cultivars were assessed for agronomic and physiological traits associated to improve the productivity in degraded acid soils under rainfed hilly ecosystem. The cultivars ICGS-76 and ICGV-86590 produced significantly (p<0.05) higher pod yield with more than 39% improvement over JL-24. The study also identified five more promising cultivars viz. ICGS-5, TKG-19 A, TG-37-A, GG-11 and GG-21 with 19-38% higher yield over the check. The low productivity of cereals in the acidic and moisture stressed Jhum degraded upland soils of rainfed hilly ecosystem of Eastern Himalayan Region is a major concern for socio-economic improvement of resource poor farmers. Adoption of these cultivars is expected to increase the productivity and net income to a tune of 93.2% without incurring any additional costs to the prevailing production system. [ABSTRACT FROM AUTHOR]

Physiology of green gram is highly sensitive to fluctuations in the thermal environment. Abnormally high temperatures during pod setting to pod development stage induces reduction in pod setting, non-healthy development and early maturity of grain which results in yield decline. We evaluated the effect of elevated temperatures in a Temperature Gradient Tunnel (TGT) on phenology, physiology and crop performance of green gram cultivars at semi-arid climate of Indian Punjab (Ludhiana). Five green gram cultivars were grown in TGT chambers in a factorial randomized block design with varying level of elevated temperatures (+3.3° C to 5.2° C) for two consecutive kharif seasons (2015-2016). The results reveal that the phenological stages of green gram, were advanced under elevated temperature within the TGT compared to open / ambient condition by 12-13 days. Maximum influence was observed in pod formation and pod maturity stages. With rise in temperatures by 3.3 to 5.2°C in TGT over ambient condition, the plant height increased but the number of branches per plant and the total above ground biomass as well as grain yield decreased consistently. It was found that with 1 oC increase in average seasonal temperature, the grain yield decreased by 75 kg ha-1. On the other hand, the harvest index was in general lower inside TGT chamber implying adverse influence of elevated temperature on biomass production although the partitioning of biomass was more efficient inside the TGT as evident from increase in harvest index. There was strong negative correlation of elevated temperature (inside TGT) with different yield attributes like 1000 seed weight, number of seeds per pod and number of pods per plant. Among the five green gram cultivars, ML-2037 was the most tolerant while cv. SML-1811 was the most susceptible to elevated temperature condition. In general, the grain yield decreased linearly with gradual increase in temperature. Average seasonal temperature of 29-30 oC may be considered as the favourable thermal conditions for the green gram crop in semi-arid conditions of Punjab. However, the future thrust will be to create more temperature gradients in the lower side so that the critical temperature threshold limits for optimum yield of green gram can be ascertained more accurately. [ABSTRACT FROM AUTHOR]

The effects of sole and intercropping of rainfed maize (Zea mays L.) were evaluated with soybean (Glycine max L.) and groundnut (Arachis hypogea L.) on crop yield, weed smothering efficiency (WSE) and nutrient (NPK) balance at Eastern Himalayan Region (EHR), India. Grain yield of maize was highest (3886 to 4110 kg ha−1) in the solitary system followed by maize-soybean intercrops at 1:2 rows. However, system productivity as well as production efficiency was higher by 47.3-63.3% and 39.5-58.4%, respectively in intercropping with groundnut at 1:5 rows compared to solitary maize. WSE was relatively higher to solitary soybean and was comparable to maize-groundnut intercropping at 1:5 row proportions. Similarly, NPK uptake was higher in intercropping of maize-soybean systems at 1:5 row proportions. Inclusion of legumes as intercrops in predominantly solitary rainfed maize may improve the system productivity while sustaining the nutrient availability in the vast uplands of the EHR and other similar rainfed hilly ecosystems. [ABSTRACT FROM PUBLISHER]

Monthly weather variables of Kolasib for past three decades were analyzed to detect the existing trend in relation to the thermal discomfort for tribal denizen in the north-eastern Indian state of Mizoram. The significant rising trend in seasonal wetness during the monsoon months was prominent, with the concomitant rise in winter dryness. The increasing trend in annual air temperature was also significant. The significant rise in Compensated Summer Ombrothermic Index (COSi) confirmed that the rising trend in monsoonal rainfall overshadowed the subsequent rise in average annual air temperature during May to September. Finally, our present study concluded the increasing possibility of degree of suffering from thermal discomfort for the residents of the Kolasib and adjacent region during the winter (viz. February) and summer monsoon months (viz May-June) in near future. [ABSTRACT FROM AUTHOR]

The topographic setting and subsistence fanning of North East India are important factors affecting the soil organic carbon (SOC) stock. We attempted to assess the SOC stock and simulated SOC under different crop management regimes at varying slope gradients in Meghalaya, India. The SOC stock at surface layer (0-15 cm soil depth) and subsurface layer (15-30 cm soil depth) was decreased in the order of potato-potato system (PPS) at 32% slope gradient of CPRS > upland rice base system (URS) at 12% slope gradient of Sawkilo > lowland rice-fallow system (LRFS) at Bhoirymbong > URS at 32% slope gradient of Pyllun. The higher SOC stock and total nitrogen (TN) was found at the surface layer whereas the soil inorganic carbon (SIC) stock was higher in the subsurface layer. The CENTURY model-simulated SOC declined at the rate of 0.1 kgm-2yr-1 at 12% and 32% slope gradient in URS of Sawkilo and Pyllun village and at the rate of 0.05 kgm-2 yr-1 in LRFS of Bhoirymbong village. However, the SOC would remain above 6 kg nr-2 in PPS at 32% slope gradient on CPRS in long run with continuation of present management practices. [ABSTRACT FROM AUTHOR]

Sagar Island, a gargantuan low-lying archipelago setting on the continental shelf of the Bay of Bengal is one of the most vulnerable deltas to climate change. Extreme climate-driven multifarious threats, including tidal gushes, deluge with sea water, permanent submergence of land, occurrence of droughts and water scarcity have taken a toll on food and environmental security of the island. Knowing the trend of long-term weather variables responsible for the climate of the island holds importance in adaptation and mitigation strategies to sustain food production. In the present article, weather variables of the island (1982-2010) have been analysed to detect the changes in trend using Mann-Kendall non-parametric test and the magnitudes of such trends have been estimated using Sen's slope. The island receives an annual average rainfall of 1735 ± 352 mm, with an inter-annual deviation exceeding 40% and exhibits a decreasing trend (-5.79 mm year-1). Significant (P < 0.05) anomalies in inter- as well intra-annual rainfall distributions (pre-monsoon, monsoon and post-monsoon months) were observed. Contribution of monsoon and post-monsoon months showed a decreasing trend (-3.84 to -4.42 mm year-1), while pre-monsoon rainfall showed an increasing trend (+ 0.98 mm year-1). Wide variability in interannual rainy days (76-139 days) and a decreasing trend (-0.24 days year-1) may further complicate the existing anomalies. The island is experiencing a significant (P < 0.05) rising trend of inter-annual mean (+ 0.021°C year-1) and maximum temperatures (+ 0.060°C year-1), with a reverse trend (decline) in minimum temperature (-0.031°C year-1). Other weather variables like sunshine duration, wind speed, atmospheric evaporative demand, etc. also manifested a complex interaction and significant (P < 0.05) decreasing trend over the study periods (1982-2010). Implications of these changes were manifested on water balance front: rising trend of water scarcity during post-monsoon months (December-February) in the island. [ABSTRACT FROM AUTHOR]

Northeastern region (NER) of India has wide variation in physiography and climatic conditions. Because of its strategic settings in the phyto-biomass-rich landscape of the Eastern Himalaya, the soils are rich in organic carbon. However, sporadic information on field-scale observations is available on soil organic carbon (SOC) content at regional level. Information on status and spatial variability of SOC and its complex interaction with land-use systems is scanty. Therefore, an attempt was made to estimate spatial variability in SOC inventories for surface soils across six states of NER (viz. Assam, Manipur, Meghalaya, Nagaland, Sikkim and Tripura covering a geographical area of 15.61 m ha) in Geographical Information System (GIS) environment. Results revealed that the soils were very high in SOC content - 98.54% area had >1% and 14.4% area had > 2.5% SOC content. Similarly, 76.5% area had SOC density of 20- 40 Mg/ha and 8% area had very high SOC density of 40-60 Mg/ha. A total of 339.8 Tg (1 Tg = 1012 g) SOC stocks was estimated on an area of 10.10 m ha surface soils representing all major land-use systems, with a major share (>50%) coming from forest soils. Complex interaction of geographic location, rainfall, soil texture and land-use practices significantly influenced spatial variation in SOC content, density and stock. The SOC content as percentage of total geographical area was highest in Sikkim followed by Nagaland, Manipur, Meghalaya, Assam and Tripura. [ABSTRACT FROM AUTHOR]