Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha...Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha, were used as materials to study the dry matter production characteristics. The super hybrid rice showed a high ability in dry matter production and accumulation and its yield enhanced with the increase of dry matter accumulation. The advantage period of dry matter production in the super hybrid rice was mainly at the middle and late growth stages compared with the check. The grain yield had no significant correlation with the dry matter accumulation before the elongation stage while had a significantly positive correlation with the dry matter accumulation from the elongation to maturity stages in super hybrid rice. There were more dry matter in vegetative organs at the heading stage in the super hybrid rice but its contribution to yield （apparent conversion percentage） was averagely 4.3 percent points lower than that in the check. For crop growth rate （CGR）, the comparative advantage of super hybrid rice was at the middle and late stages, especially after flowering. Moreover, as the rising of leaf area index （LAI） and leaf area duration （LAD）, CGR enhanced. The total LAD and the mean of lAD per day of super hybrid rice was about 14.79% and 10.31% higher than those of the check, respectively. The results indicate that the high yield of super hybrid rice mostly comes from the products of photosynthesis after heading, which is shown by the increased CGR at middle and later stages. It is suggested that LAD character might be used to better explain the advantage in the dry matter production of super hybrid rice than LAI.展开更多
To compare the grain yield and growth behaviors of hybrid rice, field experiments were conducted in a subtropical environment in Changsha, Hunan Province, China, and in two tropical environments in Gazipur and Habigan...To compare the grain yield and growth behaviors of hybrid rice, field experiments were conducted in a subtropical environment in Changsha, Hunan Province, China, and in two tropical environments in Gazipur and Habiganj in Bangladesh during 2009 to 2011. Three hybrid rice cultivars were grown under three nitrogen （N） management treatments in each experiment. The results showed that grain yield was significantly affected by locations, N treatments and their interaction but not by cultivars. Changsha produced 8-58% higher grain yields than Bangladesh locations. Sink size （spikelet number per unit land area） was responsible for these yield differences. Larger panicle size （spikelet number per panicle） contributed to greater sink size in Changsha. Aboveground total biomass was greater in Changsha than in Bangladesh locations, whereas harvest index was higher in Bangladesh locations than in Changsha. Crop growth rate （CGR） was greater at Changsha than Bangladesh locations during vegetative phase, while the difference was relatively small and not consistent during the later growth phases. Higher leaf area index and leaf area duration were partly responsible for the greater CGR in Changsha. Real-time N management （RTNM） produced lower grain yields than fixed-time N management in more than half of the experiments. Our study suggested that further improvement in rice yield in the tropical environments similar to those of Bangladesh will depend mainly on the ability to increase panicle size as well as CGR during vegetative phase, and the chlorophyll meter threshold value used in RTNM needs to be modified according to environmental conditions and cultivar characteristics to achieve a desirable grain yield.展开更多
Nitrogen and sulfur supplies have a strong influence on the physical characteristics of crop as well as on the quality and quantity of wheat storage proteins, which play an important role in bread-making process. In o...Nitrogen and sulfur supplies have a strong influence on the physical characteristics of crop as well as on the quality and quantity of wheat storage proteins, which play an important role in bread-making process. In order to evaluate the contribution of soil and foliar fertilization of nitrogen and sulfur on physiological and quality assessment of wheat, a field trail was carried out having randomized complete block design with four replications and eight different treatments of nitrogen and sulfur combinations were allotted to plots at different growth stages. Results indicated that highest protein content (12.82%), maximum moisture content (10.9%), maximum crop growth rate and maximum absolute growth rate were recorded when the wheat crop was fertilized with T8 [Nitrogen @ 60 kg·ha-1 at sowing + 40 kg·ha-1 at tillering + 10 kg·ha-1 at anthesis (spray) + 10 kg·ha-1 after anthesis (spray)] + [Sulfur @ 15 kg·ha-1 at sowing + 10 kg·ha-1 at anthesis (spray) + 5 kg·ha-1 after anthesis (spray)], while control practice resulted low moisture content, low protein, minimum crop growth rate and low absolute growth rate. Among physiological components of wheat cultivars, leaf area index was enhanced when fertilization was done with T5 (Sulfur @ 15 kg·ha-1 at sowing + 10 kg·ha-1 at anthesis + 5 kg·ha-1 after anthesis). In all the recorded observations,concerning experiment wheat cultivar Pirsabaq2005 showed appreciable response as compared with other variety (Khyber-87). Thus it is possible to obtain maximum physiological traits as well as bread-making quality of wheat through soil and foliar application of nitrogen and sulfur.展开更多
The cluster planting pattern （3 plants per hole） for cotton （Gossypium hirsutum L.） may increase economic yield over those of the traditional planting pattern （1 plant per hole） in arid regions of China. This in...The cluster planting pattern （3 plants per hole） for cotton （Gossypium hirsutum L.） may increase economic yield over those of the traditional planting pattern （1 plant per hole） in arid regions of China. This increase in yield depends on either increased biomass production or greater partitioning to fruit. This study was conducted to determine whether differences in biomass accumulation or partitioning to reproductive growth contributed to higher yield in the cluster planting pattern compared with the traditional one. Growth parameters, biomass accumulation, crop growth rate and partitioning between cluster planting pattern and traditional planting pattern was compared in northwest of China. The biomass production and partitioning in cluster planting plot was higher than in traditional planting one. Biomass accumulation was faster early in the clustered treatment, and it was also higher at harvest time. Total dry matter production per unit area was significantly higher than in the traditional planting. On a per plant basis, dry matter accumulation was faster and total biomass production was significantly higher in the cluster planting pattern. Numbers of sympodia and boll sizes were also larger, indicating that facilitation among plants was promoting crop yield. The increase in yield in the cluster planting treatment occurred through increased partitioning of dry matter to fruits than in the traditional planting pattern, resulting in more bolls and increased lint yield in arid regions.展开更多
基金the State Science and Technology Program of Grain Harvests in China (Grant Nos. 2006BAD02A06 and 2006BAD02A04)
文摘Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha, were used as materials to study the dry matter production characteristics. The super hybrid rice showed a high ability in dry matter production and accumulation and its yield enhanced with the increase of dry matter accumulation. The advantage period of dry matter production in the super hybrid rice was mainly at the middle and late growth stages compared with the check. The grain yield had no significant correlation with the dry matter accumulation before the elongation stage while had a significantly positive correlation with the dry matter accumulation from the elongation to maturity stages in super hybrid rice. There were more dry matter in vegetative organs at the heading stage in the super hybrid rice but its contribution to yield （apparent conversion percentage） was averagely 4.3 percent points lower than that in the check. For crop growth rate （CGR）, the comparative advantage of super hybrid rice was at the middle and late stages, especially after flowering. Moreover, as the rising of leaf area index （LAI） and leaf area duration （LAD）, CGR enhanced. The total LAD and the mean of lAD per day of super hybrid rice was about 14.79% and 10.31% higher than those of the check, respectively. The results indicate that the high yield of super hybrid rice mostly comes from the products of photosynthesis after heading, which is shown by the increased CGR at middle and later stages. It is suggested that LAD character might be used to better explain the advantage in the dry matter production of super hybrid rice than LAI.
基金supported by the National Basic Research Program of China (2009CB118603)the Green Super Rice (GSR) Project from the International Rice Research Institute (IRRI) for South Asia+1 种基金Project was completed through the generous cooperation of Hunan Agricultural University, Changsha, Hunan, Chinathe Bangladesh Rice Research Institute (BRRI)
文摘To compare the grain yield and growth behaviors of hybrid rice, field experiments were conducted in a subtropical environment in Changsha, Hunan Province, China, and in two tropical environments in Gazipur and Habiganj in Bangladesh during 2009 to 2011. Three hybrid rice cultivars were grown under three nitrogen （N） management treatments in each experiment. The results showed that grain yield was significantly affected by locations, N treatments and their interaction but not by cultivars. Changsha produced 8-58% higher grain yields than Bangladesh locations. Sink size （spikelet number per unit land area） was responsible for these yield differences. Larger panicle size （spikelet number per panicle） contributed to greater sink size in Changsha. Aboveground total biomass was greater in Changsha than in Bangladesh locations, whereas harvest index was higher in Bangladesh locations than in Changsha. Crop growth rate （CGR） was greater at Changsha than Bangladesh locations during vegetative phase, while the difference was relatively small and not consistent during the later growth phases. Higher leaf area index and leaf area duration were partly responsible for the greater CGR in Changsha. Real-time N management （RTNM） produced lower grain yields than fixed-time N management in more than half of the experiments. Our study suggested that further improvement in rice yield in the tropical environments similar to those of Bangladesh will depend mainly on the ability to increase panicle size as well as CGR during vegetative phase, and the chlorophyll meter threshold value used in RTNM needs to be modified according to environmental conditions and cultivar characteristics to achieve a desirable grain yield.
文摘【目的】针对绿洲灌区玉米生产水肥过量严重,灌水、施氮制度混乱等现象,揭示水氮运筹对玉米生长及产量构成的耦合效应,为构建干旱绿洲灌区玉米高产合理水肥制度提供依据.【方法】分别设3个灌水水平:低灌水水平(I_1,430 mm),中灌水水平(I_2,490 mm),高灌水水平(I_3,550 mm),和3个施氮水平:N_(1 )0 kg N/hm^2施氮水平,N_2 360 kg N/hm^2施氮水平,N_3 450 kg N/hm^2,共组成9个处理,通过田间试验研究玉米群体生长率、叶面积指数、干物质运转、光合产物对产量构成及产量的贡献机制.【结果】群体生长率在I_2、I_3处理下较I_1处理提高40.6%～67.8%,而I_2与I_3间差异不显著;N_2、N_3较N_1处理分别高17.4%和10.6%,但N_2与N_3处理间差异不显著.玉米叶面积指数在I_2、I_3处理下全生育期平均值较I_1处理分别提高29.7%和36.0%.I_2、I_3处理玉米籽粒产量分别较I_1处理高9.6%和13.7%,但是I_2、I_3处理间差异不显著;N_2和N_3处理分别较N_1处理高8.4%和10.5%,N_2和N_3处理间差异不显著.过量灌水和施氮会减少干物质向籽粒的运转,I_3处理与I_1、I_2处理比较,干物质运转量分别减少了29.4%和29.6%,对籽粒的贡献率分别降低了38.4%和32.5%;N_3分别较N_1和N_2处理干物质运转量减少了28.5%和17.1%,对籽粒的贡献率分别降低了36.1%和19.0%.综合分析,合理的灌水和施氮量对玉米籽粒产量的形成具有耦合效应,I_2N_2处理处理最终获得与I_3N_3相等的籽粒产量.【结论】灌溉定额490 mm和施氮量360 kg/hm^2处理提高了玉米光合作用对籽粒形成提供的物质补充,促进了生育前期营养器官积累的干物质向籽粒的运转量,最终获得高产,是河西绿洲灌区玉米高产适宜的水氮参数.
文摘Nitrogen and sulfur supplies have a strong influence on the physical characteristics of crop as well as on the quality and quantity of wheat storage proteins, which play an important role in bread-making process. In order to evaluate the contribution of soil and foliar fertilization of nitrogen and sulfur on physiological and quality assessment of wheat, a field trail was carried out having randomized complete block design with four replications and eight different treatments of nitrogen and sulfur combinations were allotted to plots at different growth stages. Results indicated that highest protein content (12.82%), maximum moisture content (10.9%), maximum crop growth rate and maximum absolute growth rate were recorded when the wheat crop was fertilized with T8 [Nitrogen @ 60 kg·ha-1 at sowing + 40 kg·ha-1 at tillering + 10 kg·ha-1 at anthesis (spray) + 10 kg·ha-1 after anthesis (spray)] + [Sulfur @ 15 kg·ha-1 at sowing + 10 kg·ha-1 at anthesis (spray) + 5 kg·ha-1 after anthesis (spray)], while control practice resulted low moisture content, low protein, minimum crop growth rate and low absolute growth rate. Among physiological components of wheat cultivars, leaf area index was enhanced when fertilization was done with T5 (Sulfur @ 15 kg·ha-1 at sowing + 10 kg·ha-1 at anthesis + 5 kg·ha-1 after anthesis). In all the recorded observations,concerning experiment wheat cultivar Pirsabaq2005 showed appreciable response as compared with other variety (Khyber-87). Thus it is possible to obtain maximum physiological traits as well as bread-making quality of wheat through soil and foliar application of nitrogen and sulfur.
基金supported by the National Natural Sciences Foundation of China(31300323)China Postdoctoral Science Foundation Funded Project(2014M552515)
文摘The cluster planting pattern （3 plants per hole） for cotton （Gossypium hirsutum L.） may increase economic yield over those of the traditional planting pattern （1 plant per hole） in arid regions of China. This increase in yield depends on either increased biomass production or greater partitioning to fruit. This study was conducted to determine whether differences in biomass accumulation or partitioning to reproductive growth contributed to higher yield in the cluster planting pattern compared with the traditional one. Growth parameters, biomass accumulation, crop growth rate and partitioning between cluster planting pattern and traditional planting pattern was compared in northwest of China. The biomass production and partitioning in cluster planting plot was higher than in traditional planting one. Biomass accumulation was faster early in the clustered treatment, and it was also higher at harvest time. Total dry matter production per unit area was significantly higher than in the traditional planting. On a per plant basis, dry matter accumulation was faster and total biomass production was significantly higher in the cluster planting pattern. Numbers of sympodia and boll sizes were also larger, indicating that facilitation among plants was promoting crop yield. The increase in yield in the cluster planting treatment occurred through increased partitioning of dry matter to fruits than in the traditional planting pattern, resulting in more bolls and increased lint yield in arid regions.
