Agricultural productivity is affected by air temperature and CO 2 concentration. The relationships among grain yields of dry season irrigated rice (Boro) varieties (BRRI dhan28, BRRI dhan29 and BRRI dhan58) with increased temperatures and CO 2 concentrations were investigated for futuristic crop management in six regions of Bangladesh using CERES-Rice model (DSSATv4.6). Maximum and minimum temperature increase rates considered were 0˚C, +1˚C, +2˚C, +3˚C and +4˚C and CO 2 concentrations were ambient (380), 421, 538, 670 and 936 ppm. At ambient temperature and CO 2 concentration, attainable grain yields varied from 6506 to 8076 kg·ha −1 depending on rice varieties. In general, grain yield reduction would be the highest (13% -23%) if temperature rises by 4˚C and growth duration reduction would be 23 -33 days. Grain yield reductions with 1˚C, 2˚C and 3˚C rise in temperature are likely to be compensated by increased CO 2 levels of 421, 538 and 670 ppm, respectively. In future, the highest reduction in grain yield and growth duration would be in cooler region and the least in warmer saline region of the country. Appropriate adaptive techniques like shifting in planting dates, water and nitrogen fertilizer management would be needed to overcome climate change impacts on rice production.

Previous studies (El Shaer, Omed and Axford, 1987; Akhter, Owen, Fall, O'Donovan and Theodorou, 1994) with the two-stage in vitro procedure of Tilley and Terry (1963) have shown a high correlation between digestibilities of forages as determined using either sheep rumen liquor, sheep faeces or cow faeces as the microbial inoculum. In the first study of the of the present investigation one objective was to examine the repeatability of these digestibility measurements when made on different occasions. A second objective was to assess whether the correlations between faecal and rumen fluid based inocula could be improved if microorganisms were obtained from pairs rather than individual animals. The objective in the second study using forages of known in vivo digestibility, was to investigate the effect of freezing or freeze-drying of faeces on the repeatability of digestibilities of forages determined in vitro using micro-organisms from cow faeces.

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Rice is the most important crop at the global level, as it used as a staple food in most of the countries of the world. Transplanting aged seedlings of paddy has a detrimental effect on the crop performance, which needs to be overcome for sustaining the productivity. Leaf colour chart based nitrogen application is an efficient and economical tool for enhancing the rice productivity and nitrogen use efficiency. With this in mind, a field experiment was conducted during kharif 2011, at the Research Farm of SKUAST-K, Shalimar, Srinagar (Kashmir) to optimize the seedling age of rice (Oryza sativa L.) under late transplanting conditions and to assess the suitability of using leaf colour chart as a nitrogen management tool to improve the performance of rice. The experiment was established in Randomized Block Design, with three replicates, 3 seedling ages and 6 nitrogen application treatments. The analyses of data revealed that 35 days old seedling recorded significantly higher total dry matter accumulation and dry matter partitioning to panicle (8.2 t ha-1) and leaf (2.4 t ha-1); grain yield (7.4 t ha-1); N, P and K uptake (11.6, 3.1 and 11.3 kg ha-1, respectively) (p<0.05). Among nitrogen application treatments significantly higher dry matter accumulation; yield (8.6 t ha-1) and N, P and K uptake (14.1, 3.6 and 12.7 kgha-1, respectively) was found in ½ N as basal and remaining at LCC <4 @20 kg ha-1 (p<0.05). Age of seedling and time of nitrogen application did not affect N, P, K and protein content of grain and straw significantly (p>0.05). It is concluded that the yield of rice can be improved by transplanting 35-days old seedling under late transplanted conditions in temperate regions and by following LCC guided nitrogen management.

Current techniques for in vitro digestion of forages depend on the use of rumen fistulated animals to supply microbial suspensions in rumen liquor. The objective of the present study is to develop a noninvasive alternative to rumen liquor as a source of micro-organisms in the two-stage, in vitro digestion technique of Tilley and Terry (1963).EL Shaer, Omed, Chamberlain and Axford (1987) showed a high correlation between digestibility in vitro determined using micro-organisms from rumen liquor and from freshly-voided sheep faeces. The disadvantages of using sheep faeces are (a) the need for fresh faeces, (b) the small quantities voided at any given time and (c) the difficulty of enticing sheep to defaecate at a specific time.Cow faeces as a source of micro-organisms was investigated in the present study because of the ease of collecting a large quantity of freshly-voided faeces at a given time. Another objective of the present study was to investigate whether faeces could be frozen and stored for future use as a source of micro-organisms for the in vitro digestibility assay. A further objective was to investigate whether rumen liquor could be frozen and stored for future use.