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Water and Nitrogen Management Effects on Biomass Accumulation and Partitioning in Two Potato Cultivars  [PDF]
Ashok K. Alva, Helena Ren, Amber D. Moore
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.31019
Abstract: Biomass accumulation and partitioning into different plant parts is a dynamic process during the plant growing period, which is influenced by crop management and climate factors. Adequate knowledge of biomass partitioning is important to manage the crops to gain maximum partitioning of assimilates into plant parts of economic significance, i.e. tubers in potato. This study was conducted using two potato cultivars grown in a sandy soil with center pivot irrigation under full irrigation (FI; irrigation to replenish 100% of water loss by evapotranspiration [ET]) and deficit irrigation (DI; replenish only 80% ET) and two nitrogen(N) rates (pre-plant + in-seasonN rates of 56 + 112 or 168 + 336 kg/ha). Plant samples were taken on 22, 44, 66, and 98 days after seedling emergence (DAE). With high N rate, tuber biomass of ‘Umatilla Russet’ cultivar in relation to total plant biomass varied from 23% - 88% and 25% - 86% over 22 to 98 DAE for the FI and DI treatments, respectively. The corresponding partitioning ranges were 30% - 93% and 38% - 93% at the low N rate. With respect to the‘Ranger Russet’ cultivar, biomass partitioning to tubers ranged from 36% - 82% and 23% - 84% for the FI and DI, respectively, at the high N rate, and 29% - 87% and 39% - 95% at the low N rate. Overall, this study demonstrated that within the range of N rate and irrigation treatments the biomass portioning into tubers was largely similar in both cultivars.
Analysis of water use efficiency of different winter wheat cultivars under different irrigation schemes on the basis of yield
不同灌溉条件下不同类型冬小麦产量水分利用效率差异原因分析

DONG Bao-Di,SHI Chang-Hai,QIAO Yun-Zhou,YANG Jing,ZHAI Hong-Mei,LI Dong-Xiao,LIU Meng-Yu,
董宝娣
,师长海,乔匀周,杨静,翟红梅,李东晓,刘孟雨

中国生态农业学报 , 2011,
Abstract: Five drought tolerant winter wheat cultivars were used to evaluate the differences in the effects of harvest index (HI) and biomass water use efficiency (WUEbm) on grain yield water use efficiency (WUEy) under different irrigation schemes. The wheat cultivars included dryland cultivars of "Xifeng 20" and "Jinmai 47", dry/wetland cultivar of "Shijiazhuang 8", and wetland cultivars of "Shi 4185" and "Kenong 9204". The results showed significant differences in WUEy and its changing trends among different drought tolerant wheat cultivars. Dryland cultivars had significantly lower WUEy than wetland and wet/dryland cultivars, with the highest WUEy difference of 42.01%. Average water consumption of the drought tolerant wheat cultivars was 343~350 mm. No significant difference was noted in the amount of water consumption among different cultivars. This suggested that although dryland cultivars were drought tolerant, it did not limit the rate of water consumption. It also suggested that the main factor of WUEy was WUEbm and HI. Dryland cultivars had significantly lower HI than wetland and wet/dryland cultivars, with the highest HI difference of 25.91%. Significant positive correlations were noted between HI and WUEy, and between WUEbm and WUEy. The correlation between plant height and HI was negative (R2 = 0.574). Under no irrigation, no obvious difference was noted in WUEbm among different cultivars. Dryland cultivars had lower HI than the other cultivars. The difference in WUEy among different cultivars was driven by the differences in HI. Under supplemental irrigation conditions, however, wetland and wet/dryland cultivars had higher WUEbm and HI than dryland cultivars. The differences in WUEy came mainly from interactive effects of HI and WUEbm. The results suggested that different drought-tolerant wheat cultivars had responded differently to the same condition and therefore had different adaptation strategies to environmental conditions. Dryland cultivars enhanced WUEbm which in turn led to higher WUEy in extreme drought conditions. Wetland and wet/dryland cultivars, on the other hand, enhanced HI and WUEbm to yield higher WUEy under supplemental irrigation conditions.
Effects of limited irrigation on yield and water use efficiency of two sequence-replaced winter wheat in Loess Plateau, China
L Liu, B-C Xu, F-M Li
African Journal of Biotechnology , 2007,
Abstract: The effects of irrigation on grain yield and water use efficiency was studied on two sequence replaced dryland winter wheat (Triticum aestivum L.) cultivars, Changwu 135 (CW, a new cultivar) and Pingliang 40 (PL, an old cultivar). Field experiments were carried out on Changwu country on Loess Plateau, China. Whereas the control plots were not irrigated at all, the treatment plots were irrigated three times, the quantity of irrigation being the same (40 mm) each time: at the jointing stage, at booting, and at flowering. Irrigation increased root biomass in each layer of soil in PL. Irrigation made PL produce greater root biomass in deeper soil, enabling the plants to tap larger quantities of water. CW had a harvest index (HI) greater by 0.11 than that of PL under both conditions, and lower shoot and root biomass, which indicates that more dry matter was transported to productive organs, leading to higher yields than PL. CW consumed more water to produce a unit quantity of root biomass and use irrigation less efficiently showing undercompensation, whereas PL showed overcompensation. Higher yield and greater water use efficiency in wheat appear to be associated with smaller root systems and higher harvest index irrespective of irrigation.
Relationships between grain yield and accumulation of biomass, nitrogen and phosphorus in common bean cultivars
Araújo, Adelson Paulo;Teixeira, Marcelo Grandi;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000500019
Abstract: shoot biomass is considered a relevant component for crop yield, but relationships between biological productivity and grain yield in legume crops are usually difficult to establish. two field experiments were carried out to investigate the relationships between grain yield, biomass production and n and p accumulation at reproductive stages of common bean (phaseolus vulgaris) cultivars. nine and 18 cultivars were grown on 16 m2 plots in 1998 and 1999, respectively, with four replications. crop biomass was sampled at four growth stages (flowering r6, pod setting r7, beginning of pod filling r8, and mid-pod filling r8.5), grain yield was measured at maturity, and n and p concentrations were determined in plant tissues. in both years, bean cultivars differed in grain yield, in root mass at r6 and r7 stages, and in shoot mass at r6 and r8.5, whereas at r7 and r8 differences in shoot mass were significant in 1998 only. in both years, grain yield did not correlate with shoot mass at r6 and r7 and with root mass at r6. grain yield correlated with shoot mass at r8 in 1999 but not in 1998, with shoot mass at r8.5 and with root mass at r7 in both years. path coefficient analysis indicated that shoot mass at r8.5 had a direct effect on grain yield in both years, that root mass at r7 had a direct effect on grain yield in 1998, and that in 1999 the amounts of n and p in shoots at r8.5 had indirect effects on grain yield via shoot mass at r8.5. a combined analysis of both experiments revealed that biomass accumulation, n and p in shoots at r6 and r7 as well as root mass at r6 were similar in both years. in 1998 however bean accumulated more root mass at r7 and more biomass and n and p in shoots at r8 and r8.5, resulting in a 57 % higher grain yield in 1998. this indicates that grain yield of different common bean cultivars is not intrinsically associated with vegetative vigor at flowering and that mechanisms during pod filling can strongly influence the final crop yield. the esta
WHEAT CULTIVARS: RESPONSE TO IRRIGATION AND SOWING DATES
Klar, A.E.;Hossokawa, T.;
Scientia Agricola , 1996, DOI: 10.1590/S0103-90161996000200004
Abstract: this study was carried out in an alfisol-oxisol transition sandy-clay texture, using six wheat cultivars (triticum aestivum, l.): two tall and tolerant to soil aluminium toxicity (bh-1146, and iac-18), and four semi-dwarf cultivars - anahuac, iac-162, iac-24, and iac-60 - of which only the first two are sensitive to soil aluminium toxicity. two minimum soil water potentials (ys) levels were used: 1. watered, when ys reached about -0.05 mpa; 2. dry, when the water potential reached around -1.5 mpa. two sowing dates, 05/22/92 and 06/11/92, were used. the results showed that anahuac and iac-60 are the most indicated cultivars for the studied region; when irrigated all cultivars presented similar yield level under no irrigation conditions; the irrigation was not sufficient to avoid yield differences between the two growing seasons; differences in rainfall were important for the crop in the dry treatment for both seasons.
WHEAT CULTIVARS: RESPONSE TO IRRIGATION AND SOWING DATES  [cached]
Klar A.E.,Hossokawa T.
Scientia Agricola , 1996,
Abstract: This study was carried out in an Alfisol-Oxisol transition sandy-clay texture, using six wheat cultivars (Triticum aestivum, L.): two tall and tolerant to soil aluminium toxicity (BH-1146, and IAC-18), and four semi-dwarf cultivars - Anahuac, IAC-162, IAC-24, and IAC-60 - of which only the first two are sensitive to soil aluminium toxicity. Two minimum soil water potentials (ys) levels were used: 1. watered, when Ys reached about -0.05 MPa; 2. dry, when the water potential reached around -1.5 MPa. Two sowing dates, 05/22/92 and 06/11/92, were used. The results showed that Anahuac and IAC-60 are the most indicated cultivars for the studied region; when irrigated all cultivars presented similar yield level under no irrigation conditions; the irrigation was not sufficient to avoid yield differences between the two growing seasons; differences in rainfall were important for the crop in the dry treatment for both seasons.
不同冬小麦品种超晚播节水栽培的物质积累和水分利用特征
Characteristics of biomass production and water use in different winter wheat cultivars under extremely-late sown and water-saving cultivation
 [PDF]

王彬,张俊丽,徐学欣,张英华,王云奇,赵姣,王志敏
- , 2017,
Abstract: 为探究超晚播条件下不同品种冬小麦的物质积累和水分利用特征,采用3个不同穗型冬小麦品种(小穗型衡水4399;大穗型潍麦8号;中间型济麦22)在黑龙港地区进行了连续3年的大田试验。结果表明,超晚播配合增加播种量,春浇1水可以获得产量为6.43~8.24 t/hm2。在3个品种中,济麦22产量和水分利用效率最高。品种间产量的差异主要是粒重差异引起的。济麦22较高的千粒重和产量与其较高的开花期穗生物量分配、花后物质积累和收获指数密切相关。济麦22花前水分的穗干物质生产效率、花后水分的干物质生产效率和籽粒干物质生产效率均显著高于潍麦8号和衡水4399,从而获得了最高的水分利用效率。综合分析表明,穗型中等、花后物质积累和水分生产力高的品种更适合于超晚播节水栽培。
In order to investigate characteristics of biomass production and water of different winter wheat cultivars,a three-year field experiment was conducted on three cultivars with different spike types (small spike cultivar Hengshui 4399,large spike cultivar Weimai 8 and medium spike cultivar Jimai 22) in low champaign area of Heilonggang,which were sown on extremely-late sowing date.The results showed that yield of 6.43-8.24 t/hm2 was obtained in extremely-late sown winter wheat under one irrigation regime combined with increased seeding amount.Among the three cultivars,yield and water use efficiency were the highest in cultivar Jimai 22.The highest yield in Jimai 22 was largely determined by the highest 1 000-grain weight,which were associated with the highest biomass partitioning in spike at anthesis,post-anthesis biomass and harvest index in Jimai 22.Water use efficiency for spike biomass at anthesis,post-anthesis biomass and grain biomass at maturity were higher in Jimai 22 than in other two cultivars,resulting in the highest water use efficiency in Jimai 22.In conclusion,cultivar with medium spike,high biomass and water productivity post-anthesis is better adapted to extremely-late sown and water-saving cultivation.
Effect of Supplemental Irrigation and Amount of Available Water on Yield, Yield Components and Physiological Characteristics of Two Rainfed Wheat Cultivars
M.R. Tadayon,Y. Emam
Journal of Science and Technology of Agriculture and Natural Resources , 2008,
Abstract: Photosynthesis and wheat grain yield responses to supplemental irrigation with different amount of applied water under dryland conditions were investigated. Therefore, a two-year field experiment was conducted research farm of College of Agriculture, Shiraz University during 2004-2005. Five levels of irrigation including dryland conditions, irrigation at stem elongation, booting, flowering and grain filling were main plots and two wheat cultivars: Agosta and Fin-15 were subplots, and three rates of nitrogen including zero, 40 and 80 kgha-1 were sub sub-plots. The results showed that in both years, photosynthetic rate, stomatal conductance, substomatal CO2 concentration and transpiration rate, were significantly higher under irrigation at stem elongation stage compared to other supplemental irrigation treatments. In all of the four supplemental irrigation treatments, photosynthetic rate, stomatal conductance, substomatal CO2 concentration and transpiration rate decreased with decreasing the amount of applied water to each plot. In both years, the highest grain yield was obtained from supplemental irrigation at stem elongation stage, and the lowest yield was harvested at dryland conditions. The highest photosynthetic parameters, yield and yield components were obtained from interaction of supplemental irrigation at stem elongation stage × Fin-15 and 80 kg N ha-1 in both years. The supplemental irrigation in 2004 and 2005 increased the grain yield 200 and 221 percent, respectively, compared to dryland conditions. Thus, supplemental irrigation at sensitive stem elongation stage could affect significantly wheat grain yield of rainfed wheat cultivars and provision of adequate water for a supplemental irrigation at the appropriate growth stage could double the grain yield of rainfed wheat.
Influence of Different Irrigation Regimes on the Phenology and Accumulated Heat Units in Four Bread Wheat Cultivars
M.Z. Alam,S.A. Haider,N.K. Paul
Pakistan Journal of Biological Sciences , 2004,
Abstract: A field investigation was carried out to study the influence of irrigation on phenology and accumulated heat units of four cultivars of bread wheat (Triticum aestivum L.) at different phenological stages over two growing seasons. There were three treatments: rainfed, 10 and 20 mm irrigation. The rainfed plants had significantly shorter phenological stages and lower growing day degree than the irrigated plants in all the four cultivars. Cultivars Akbar was found to be early and C 306 was found to be late maturing. Akbar had the lowest and C 306 had the highest growing degree days during all the phenological stages under each irrigation regime. Heliothermal units also showed more or less the same trends. The phenothermal indices and heat use efficiency were found to be higher in the irrigated plants than the rainfed plants.
Performance of Roselle (Hibiscus sabdariffa L) as Influenced by Irrigation Schedules  [PDF]
F.E. Babatunde,A.L.E. Mofoke
Pakistan Journal of Nutrition , 2006,
Abstract: Global outcry for food security necessitates both rain fed and irrigation farming to boost up world food production. This research therefore explored the possibility of growing roselle (Hibiscus sabdarriffa. L) under irrigation. The experimental treatments comprised five irrigation schedules with irrigation intervals (f) of 3, 5, 7, 9, and 11 days. The corresponding gross water requirements (GWR) were 37, 56, 74, 93, and 112mm. The crops were grown under check basin irrigation during the 2001/2002 and 2002/2003 irrigation seasons in Bauchi state, Nigeria. Results showed that difference in number of leaves per plant was significant (p = 0.05) with the fifth irrigation schedule (f = 11 days, GWR = 112mm) giving the highest value of 347 leaves per plant, while the first irrigation schedule (f = 3 days, GWR = 37mm) resulted in only 192 leaves per plant. Variations in plant height, number of branches per plant and canopy diameter were insignificant (p = 0.05). The influence of irrigation schedule on the yield of roselle measured with respect to fresh calyx weight was highly significant with a strong coefficient of determination of 97.1%. Yield soared with increase in seasonal irrigation depth. The increase followed a second degree polynomial, reaching a projected maximum of about 682 Kg/ha. The associated maximum seasonal application depth was found to be approximately 3389 mm. Results of this study indicate that maximum yield of roselle grown under irrigation could be attained with a weekly irrigation interval and a gross application depth of 188 mm.
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