ABSTRACT
To explore a new technique of planting wheat with high yield and efficiency by mulching technology in rain-fed semiarid regions in Northwest China, a two-year fixed-site trail was conducted during 2013-2015. There were five mulching modes: (1) three sowing rows by bundled straw mul-ching with alternating 30-cm-wide mulching belt and planting belt (SM1), (2) four sowing rows by bundled straw mulching with alternating 40-cm-wide mulching belt and planting belt with (SM2), (3) five sowing rows by bundled straw mulching with alternating 50-cm-wide mulching belt and planting belt (SM3), (4) whole plastic film mulching with dibbling (PMF), (5) bare field planting without any mulching (CK). We examined the effects of different mulching modes on water consumption, water use efficiency (WUE), and yield of winter wheat in rain-fed region in Northwest China. The results showed that bundled straw mulching significantly increased soil water storage. Soil water storage with bundled straw mulching was remarkably higher than that with the whole plastic mul-ching with SM1ï¼SM2ï¼SM3. Soil water storage at 0-200 cm soil layer in flowering period was increased by 15.4%-20.8%,11.2%-14.7%and 10.1%-14.5% respectively over that in the bare field. Bundled straw mulching significantly increased water consumption during the whole growing period while reduced water consumption from sowing and flowering periods. Further, it increased water consumption from flowering to maturity periods and the ratio of water consumption during this period to the total water consumption during the whole growing periods. The results showed that mulching could increase the consumption ratio of deep water storage from the soil layer below 120 cm. Compared with CK, PMF and SM significantly increased grain yield and water use efficiency by 11.9%-19.5%, 26.9%-27.1%, respectively, and increased water use efficiency by 9.8%-13.9%, 18.4%-22.0% respectively. In all, bundled straw mulching could reduce water consumption ratio in the early growing periods, improve moisture condition, increase grain yield and water use efficiency of winter wheat. Therefore, we concluded that bundled straw mulching is an environment-friendly cultivation technology suitable for the winter wheat in semi-arid region of the Loess Plateau in Northwest China.
Subject(s)
Drinking , Triticum , Agriculture , China , Rain , Soil , WaterABSTRACT
To evaluate the effects of straw belt-covering on soil temperature and yield of winter wheat in rain-fed semiarid region in Northwest China, five mulching modes, including flat field planting without any mulching (CK), whole plastic film mulching (PM), straw mulching by 30 cm covering belt with an interval of 30 cm planting belt with three-row sowing (SM1), straw mulching by 40 cm covering belt with an interval of 40 cm planting belt with four-row sowing (SM2), and straw mulching by 50 cm covering belt with an interval of 50 cm planting belt with five-row sowing (SM3), were set by two-year fixed-site trails in 2013-2015. The results showed that soil temperature significantly varied among different growth stages and soil layers in all treatments. SM1, SM2 and SM3 significantly decreased soil temperature by 1.0-1.3 â, 0.7-0.9 â and 0.7-1.1 â in the 0-25 cm soil layer, respectively. The mulching had double effects with increasing and decreasing soil temperatures. The straw mulching significantly increased soil temperature in the duration of seedling to overwintering stage, but greatly decreased soil temperature in the duration of reviving to mature stage. The temperature-increasing effect of film mulching was stronger than that of straw mulching, which was opposite to the temperature-decreasing effect. Straw mulching significantly reduced in the effective accumulated temperature and the daily temperature variations during the whole growth stages. The effective accumulated temperature under straw mulching decreased by 3.4-33.5 â·d, and the soil temperature difference decreased by 0.6-2.0 â. During over-wintering stage, the straw mulching showed a higher average soil temperature (0.2-0.3 â) and negative accumulated temperature (0.4-17.0 â·d) than those under the CK. The straw mulching significantly increased grain yield by 11.9%-19.5%. The variations of spikes per unit area were the main factor responsible for yield difference. The findings indicated that that straw mulching method is suitable for winter wheat production in rain-fed region of Northwest China.
Subject(s)
Agriculture/methods , Soil/chemistry , Temperature , Triticum/growth & development , China , Rain , WaterABSTRACT
Based on the grain yield data of regional trials with 233 winter- and spring wheat cultivars (lines) in rainfed farmlands at 82 locations in four subregions of China in 2003-2009, this paper studied the experiment precision (EP), variety comparison precision (VCP), and testing-site discrimination ability and representativeness of national regional trials, and comprehensively evaluated the trial environment. The results showed that in one-location-one-year experiments, the average coefficient of variation (CV) and the relative least significant difference (RLSD) were 6.1% and 10.5%, respectively, and in multi-location-one-year experiments, the CV was all within 8.2%, and the CV and RLSD were mostly well controlled, indicating that the trials had a high precision. The testing-site discrimination ability was the highest in the northwest spring wheat subregion, but showed less difference in the other subregions. The testing-site representativeness was the best in the northeast spring wheat subregion, and the worst in the northwest spring wheat subregion. On the basis of the comprehensive consideration of the testing-site discrimination ability and representativeness, and by using the parameters of the environmental comprehensive assessment (r(g)h) of GGE model, it was shown that the proportion of the ideal trial locations for wheat in our rainfed farmlands was only 32.4%. Among the wheat production regions, the proportions of the ideal trial locations were in the order of northwest spring wheat subregion (40.9%) > northeast spring wheat subregion (33.3%) > Huang-Huai winter wheat subregion (30.4%) > north winter wheat subregion
