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In this study, we assessed the possible impacts of climate variability and change on growth and performance of maize using multi-climate, multi-crop model approaches built on Agricultural Model Intercomparison and Improvement Project (AgMIP) protocols in five different agro-ecological zones (AEZs) of Embu County in Kenya and under different management systems. Adaptation strategies were developed that are locally relevant by identifying a set of technologies that help to offset potential impacts of climate change on maize yields. Impacts and adaptation options were evaluated using projections by 20 Coupled Model Intercomparison Project—Phase 5 (CMIP5) climate models under two representative concentration pathways (RCPs) 4.5 and 8.5. Two widely used crop simulation models, Agricultural Production Systems Simulator (APSIM) and Decision Support System for Agrotechnology Transfer (DSSAT) was used to simulate the potential impacts of climate change on maize. Results showed that 20 CMIP5 models are consistent in their projections of increased surface temperatures with different magnitude. Projections by HadGEM2-CC, HadGEM2-ES, and MIROC-ESM tend to be higher than the rest of 17 CMIP5 climate models under both emission scenarios. The projected increase in minimum temperature (Tmin) which ranged between 2.7 and 5.8°C is higher than the increase in maximum temperature (Tmax) that varied between 2.2 and 4.8°C by end century under RCP 8.5. Future projections in rainfall are less certain with high variability projections by GFDL-ESM2G, MIROC5, and NorESM1-M suggest 8 to 25% decline in rainfall, while CanESM2, IPSL-CM5A-MR and BNU-ESM suggested more than 85% increase in rainfall under RCP 8.5 by end of 21st century. Impacts of current and future climatic conditions on maize yields varied depending on the AEZs, soil type, crop management and climate change scenario. Impacts are largely negative in the low potential AEZs such as Lower Midlands (LM4 and LM5) compared with the high potential AEZs Upper Midlands (UM2 and UM3). However, impacts of climate change are largely positive across all AEZs and management conditions when CO2 fertilization is included. Using the differential impacts of climate change, a strategy to adapt maize cultivation to climate change in all the five AEZs was identified by consolidating those practices that contributed to increased yields under climate change. We consider this approach as more appropriate to identify operational adaptation strategies using readily available technologies that contribute positively under both current and future climatic conditions. This approach when adopted in strategic manner will also contribute to further strengthen the development of adaptation strategies at national and local levels. The methods and tools validated and applied in this assessment allowed estimating possible impacts of climate change and adaptation strategies which can provide valuable insights and guidance for adaptation planning. [ABSTRACT FROM AUTHOR]

Cardiac Lipomas, accounting for 10% of primary benign cardiac tumours are usually asymptomatic, although they can sometimes be associated with a plethora of manifestations. Our patient was a 16 year old asymptomatic female with marked lipomatous hypertrophy of the interventricular septum protruding into the right ventricle, diagnosed incidentally during the ECHO evaluation for a haemic systolic murmur.

The impact of future climate change on the chickpea productivity was studied using the sequence analysis tool of DSSAT V 4.5 to simulate fallow-chickpea rotation at four locations viz Anantapur, Kurnool, Kadapa and Prakasam of Andhra Pradesh State. The results indicated that as compared to baseline climate, the climate change to be anticipated by 2069 (Mid -century period) would decrease the yield of chickpea by 4.3 to 18.6 per cent across various locations tested. Yield benefits obtained based on the simulation study from various adaptation options revealed that advancing the sowing window by one fortnight and application of one critical irrigation at 60 DAS found to be beneficial in increasing chickpea yields under climate change scenario. [ABSTRACT FROM AUTHOR]

The sustainability of traditional rice (Oryza sativa L.) cultivation in many Asian countries is being questioned due to severe water shortage conditions, envisaging the need for development of water-saving rice production technologies. A 2-year-field study on a typic Haplustalf soil was conducted to compare traditional transplanted rice-maize system with water-saving aerobic rice-maize system, with an overall objective of investigating the fate of fertilizer nitrogen (N) using N-labeled urea. Results from the field experiments showed that the rice plants positively responded to N fertilizer application. The average fertilizer N recovery by rice crop over the 2 years in aerobic rice was 26 kg per 100 kg of applied fertilizer N in the main field and 21 kg per 100 kg of applied N in the microplot, while the recoveries were 41 and 32 kg ha per 100 kg of applied N in traditionally cultivated rice under flooded conditions. The fraction of N that was found in soil after the harvest of rice crop ranged from 11.4 to 47.1 kg ha in aerobic rice and 14.2-51.4 kg ha in flooded rice. Average recovery of N fertilizer in maize after the first growing season was 3.3 %, and the corresponding recovery in soil was 19 %. An additional 1.3 % of the fertilizer was recovered by crops during the two subsequent seasons. This study indicates the need to develop management practices that improve N use efficiency in aerobic rice by reducing losses to improve yields and reduce N export to the environment. [ABSTRACT FROM AUTHOR]

Limited water availability is a major constraint for cultivation of rice (Oryza sativa L.) in the traditional flooded systems, particularly in the semiarid regions of the world. Aerobic rice cultivation provides feasible alternative to traditional rice production in these regions, allowing significant water savings. Field experiments were conducted at the ANGR University Agricultural Research Station, India during 2009-2010 and 2010-2011 to compare crop growth, yield, and water savings under aerobic rice-maize (R-M) and flooded R-M rotation systems. The effect of aerobic rice on the succeeding maize crop was also studied. The total amount of water applied (including rainfall) in the aerobic plots was 967 and 645 mm compared to 1546 and 1181 mm in flooded rice system, during 2009 and 2010, respectively. This resulted in 37 to 45% water savings with the aerobic method. The soil moisture in aerobic treatment was maintained in the - 3 0 to - 4 0 kPa range throughout the crop growth. The aerobic rice system produced significantly lower grain yields in 2009 and 2010, where differences between flooded and aerobic rice were 39 and 15.4%, respectively. The yield differences were attributed to the differences in spikelet number per panicle and grain weight. Significant increase in yields was recorded in both systems with increased N rates up to 120 kg ha-1. Significantly higher yields were obtained in no-till maize grown subsequent to the aerobic rice than flooded rice, possibly due to residual soil N and improved soil physical conditions. [ABSTRACT FROM AUTHOR]