Uk Sarker

Effects of Mulching on Growth and Yield Components of Selected Varieties of Wheat (Triticum Aestivum L.) under Field Condition

Received: 20 January 2018 Revised received: 11 February 2018 Accepted: 20 February 2018 Wheat is facing increased high temperature during its grain filling period in Bangladesh which reduces yield drastically. Mulching may help to mitigate this problem. Therefore, a field experiment was carried out at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during the period from November 2015 to March 2016 to find out growth and yield performance of wheat as influenced by mulching. The experiment comprised of two factors viz., variety and mulching. The variety comprised of BARI Gom-26, BARI Gom-27 and BARI Gom-28. Mulching comprised of four different levels of treatments viz.no mulch + no irrigation (control), water hyacinth mulch + no irrigation, rice straw mulch + no irrigation and two irrigations at CRI and flowering stage. The experiment was laid out in a randomized complete block design with three replications. BARI Gom-28 showed the highest values in growth parameters (plant height, number of total tillers hill, LAI, chlorophyll content and total dry matter) at 30, 45 and 60 DAS. On the other hand, when mulching was compared, rice straw mulch gave higher yield compared to other treatments at 30, 45 and 60 DAS. The interaction effect of variety and mulching showed significant in relation to yield and yield components except plant height, spike length, 1000grain weight and harvest index (%). The tallest plant (93.20 cm) was obtained from the interaction of BARI Gom-28 and rice straw mulch. The highest number of total tillers hill (4.80), number of effective tillers hill (4.57), spike length (10.23), number of spikelets spike (21.15), 1000-grain weight (48.54 g), grain yield (5.20 t ha ), straw yield (7.27 t ha), and harvest index (41.71%) were obtained from the interaction of BARI Gom-28 and rice straw mulch. The lowest grain yield was obtained from BARI Gom-26 and control (no mulch + no irrigation). It may be concluded from the results of the study that, BARI Gom-28 with rice straw mulching treatment can be used for successful cultivation of wheat.

Physiological Parameters and Yield Differ in Rice ( Oryza sativa L.) Cultivars with Variable Water Management Systems

In recent years, agriculture is facing two major challenges that include enhancement of food production sustainably to feed a growing world population and this increment needs to be accomplished under conditions of increasing scarcity of water resources (Bouman, 2007). Rice (Oryza sativa L.) is the principal staple food for more than 50% of the world’s population (Jahan et al., 2017). The world’s farmers have to produce about 60% more rice than at present to meet up the food demands of the expected world population by 2025 (Fageria, 2007). Rice production under irrigated condition is the leading consumer of water in the agricultural sector, and its sustainability is intimidated by increasing water scarcity. In consequence, rice production in Asia is increasingly constrained by water limitation (Arora, 2006) and increasing pressure to reduce water use in irrigated production as a consequence of global water crisis (Tuong and Bouman, 2002). Irrigated lowland rice consumes more than 50% of total freshwater, and irrigated flooded rice requires two or three times more water than other cereal crops, such as wheat and maize (Barker et al., 1998; Sarkar et al., 2017). For 1 kg of rice, it is estimated that farmers use 3 to 4 thousand litres of water whereas it actually needs 1.0 to 1.5 thousand litres only. Thus, for irrigation farmers have to pay about 30-40% of the extra cost. This might be due to their ignorance about the need of water for rice cultivation as well as consequence of misuse of water. In addition, rice production is facing increasing competition with rapid urban and industrial development in terms of freshwater resource (Bouman and Tuong, 2001). The need for “more rice with less water” is crucial for food security, and irrigation plays a greater role in meeting future food needs than it has in the past (Tuong et al., 2005). This issue will necessitate the development of substitute irrigated rice production systems that involve less water than conventional flooded rice (Bouman et al., 2005). Different water saving techniques for rice production have been evolved by researchers such as alternate wetting and drying (AWD) (Bouman and Tuong, 2001; Belder et al., 2004), saturated soil culture (Tuong et al., 2005), direct dry seeding (Tabbal et al., 2002; Rahman, 2016), and aerobic rice culture (Bouman et al., 2005; Kato et al., 2009). These have been found to be effective in reducing water use and improving water productivity, but there are debates on whether these water-saving techniques will increase or decrease rice yields (Bouman et al., 2007). The lower productivity of rice is associated with drought stress arises from these technologies. This stress has now become a severe threat to ensure food ORIGINAL RESEARCH ARTICLE