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1.
2015年在四川省德阳市进行大田水稻直播试验,以早稻、早熟中稻、中熟中稻、迟熟中稻等4种类型水稻品种为材料,设置3个播期茬口(前茬作物分别为蔬菜、油菜和小麦),研究不同茬口和品种类型对直播稻产量形成的影响,为茬口及品种类型的科学搭配提供依据。结果表明,随着播期的推迟,水稻播种至齐穗、齐穗至成熟的生育期缩短;早稻、早熟中稻、中熟中稻的产量先增加后下降,迟熟中稻的产量显著降低。蔬菜茬口和油菜茬口以中熟中稻的产量最高,分别为8.47 t/hm~2和9.30 t/hm~2,小麦茬口则以早熟中稻的产量最高,为7.99 t/hm~2。随着播期的推迟,早熟中稻、中熟中稻的干物质积累量呈先增加后降低的趋势,而早稻、迟熟中稻的干物质积累量呈降低趋势。由此可见,成都平原蔬菜茬口和油菜茬口水稻直播以选用中熟中稻品种较为适宜,小麦茬口水稻直播则选用早熟中稻较好。  相似文献   

2.
Agricultural production in the coastal wetlands of Asia is often hindered by salinity intrusion caused by tidal fluctuation. This paper reports changes in environmental and socio-economic conditions that followed the phased construction and operation of sluices for controlling seawater intrusion from 1994 –2000 in a coastal area of the Mekong River Delta, Vietnam. Canal water salinity decreased rapidly upstream of sluices, allowing rice cropping intensification and increased rice production in the eastern part of the study area. However, the livelihoods of farmers in the western part were adversely affected due to cessation of supply of brackish water that was needed for brackish-water shrimp farming, while the acid sulphate soils present there posed problems for rice cultivation. The poor farmers and landless people suffered more because the fishery resource that they depended on declined sharply due to reduced salinity and increased acidity in the canal water. The findings confirmed that the environment and resource use in the coastal lands are very sensitive to external intervention. A clear understanding of the socio-economic and environmental impacts of salinity control measures in coastal areas can help planning to enhance farmers' incomes while minimizing negative environmental impacts. Land-use policy formulation, planning and management should adopt a more holistic approach, taking into account the interests of all resource users, especially the poor, instead of focusing on any particular sector.  相似文献   

3.
我国华北地区粳稻品种抽穗期遗传分析   总被引:3,自引:2,他引:1  
 设置长、短日照和高、低温共4种环境,分析了我国华北地区14份主栽粳稻品种的抽穗期光、温敏感性及基本营养性。结果表明,华北地区多数粳稻品种表现出感光性,但感光性大都偏弱,抽穗期长短与品种的感光性呈显著线性相关。此外,大多数品种对温度也比较敏感。并利用一套抽穗期主基因近等基因系对这些品种抽穗期基因型进行了分析。结果表明,所有华北地区粳稻品种都携带主效感光基因E1,而在Se 1位点,有11个品种为非感光的Se 1e,同时,有13个品种都携带早熟基因Ef 1,另外,有9个品种还携带具有一定感光抑制效应的hd2。这些结果从基因型角度揭示了华北地区粳稻品种具有一定的感光性和较短的基本营养生长期的原因,为华北地区选育适宜抽穗期的粳稻品种提供了依据。  相似文献   

4.
Heading date is one of the most important traits for rice adaptation to cultivation area and crop seasons, and it is mainly determined by photoperiod, basic vegetative growth, and temperature of cultivars. The diversity of combinations of photo-sensitive varieties and the basic vegetative, makes the heading date varied. On one hand, this supplies abundant resources for different ecotypes breeding; on the other hand, it complicates the inheritance of heading date. In recent years, transgression of late maturity has often been encountered, especially between indica and japonica subspecies, this had inhabited the use of hybrid vigor. Therefore, understanding the inheritance basis of heading date is very important for breeding practices.  相似文献   

5.
不同土壤水分含量对水稻水分利用特征的影响   总被引:5,自引:0,他引:5  
 采用控制土壤水分含量的盆栽实验,研究了土壤水分含量对水稻水分利用特性的影响。结果表明,常规水作累积耗水量显著高于覆膜未淹水处理,但稍低于覆膜淹水处理;覆膜轻度水分胁迫或无胁迫处理不仅能够维持和提高产量,水分利用效率也有所提高。随着土壤水分含量的降低,全生育期水稻累积耗水量、各生育期耗水量及耗水强度逐渐降低,且田间持水量与全生育期累积耗水量呈极显著二次曲线相关。无水分胁迫覆膜处理下拔节孕穗期耗水量及模比系数高于其他生育期,其他处理耗水量和模比系数在乳熟期最高。随着土壤水分含量降低,抽穗开花期前各生育期水稻耗水模比系数有降低趋势,其后则有升高趋势;耗水强度下降;有效穗数和实粒数减少,产量逐渐降低,水分生产率先上升后下降。水稻产量与水分利用率具有显著二次曲线相关性。  相似文献   

6.
寒地水稻的产量和品质受当地气温条件所左右。对佳木斯市近期二十年的气温实测资料做了统计分析,并计算出当地水稻主栽品种各生育阶段的活动积温,结合水稻生育界限温度等资料,绘制了水稻计划栽培图。以安全抽穗期为中心,确定了当地水稻栽培各主要生育阶段的界限时期、提出了适宜种植品种,以便充分利用当地热能资源,防御低温冷害,而实行计划栽培,为水稻生产安全成熟,提高品质和产量。  相似文献   

7.
Sustainability of irrigated agriculture in the semi-arid regions such as the rice growing regions of the southern Australia could be under serious threat due to recharge to saline groundwater leading to secondary salinisation. This paper presents two approaches to reduce net recharge to shallow saline groundwater from ponded rice cropping systems using a soil, water and groundwater management model–SWAGMAN model. First approach applies the concept of growing deep-rooted crop (crop consuming water from soil and shallow water table) over an area equivalent to recharge from a unit area of rice crop to maintain the total water balance. The second approach involves achieving whole farm water balance for average and wet climatic conditions to find out optimum cropping pattern to minimise recharge from rice based system. Results of both approaches are sensitive to water table depth and regional groundwater outflow rates. The first approach was applied to determine an optimal mix of rice/lucerne crop to keep water tables and average soil salinity changes less than 0 m/year and 0.015 dS/m, respectively. The area of lucerne required to match the net groundwater rise caused by 1 ha of rice is 1.27, 2.45 and 3.55 ha for 1, 0.5 and 0.2 ML/ha regional groundwater outflow capacity. Results from second approach revealed that it is possible to control net recharge under above average rainfall using a suitable whole farm cropping mix e.g. 50 ha rice–wheat rotation, 19 ha rice, 25 ha of lucerne and 136 ha of fallow.  相似文献   

8.
武夷山风景区周边盆地属中亚热带气候,水稻安全生长季235d,积温5368℃,可一年两熟,种植晚熟高产杂交稻品种的热量一季有余,两季不足。适时早播,调节单季稻和再生稻头季开花结实期与七八月份光温高值期重合,再生季避过早秋冷害,是稻作增产增收的关键举措。高产配套技术有选用良种、合理施肥管水、推行机械化生产和防控病虫草害。  相似文献   

9.
Rain-fed lowlands are major agricultural ecosystems used for rice production in Northeast Thailand. Developing a tool to assess the effects of variable water conditions on the regional scale yield is also important to predict the effects of climate change on food supply. To estimate regional yields, we need a simple but accurate measure of the crop calendar (i.e., the distribution of planting dates), which has a strong influence on grain yield. In this article, we modeled the dependence of the crop calendar on rainfall patterns based on a survey of the region’s farmers as a part of an effort to provide a stronger basis for regional yield estimates. Our survey, conducted in 11 provinces for 2 years, confirmed the existence of large windows for sowing and transplanting versus narrow windows for heading and harvesting for rain-fed lowland rice culture in all the provinces. Variable water, soil, and toposequential conditions in the paddy fields were responsible for the large sowing and transplanting windows, whereas the use of photoperiod-sensitive varieties explained the narrow windows for heading and harvesting. The crop calendar was well expressed as a function of cumulative precipitation from June onward. When the crop calendar model was combined with a simple phenology-based model that uses growing degree-days adjusted by a day-length factor, we could estimate the rice crop calendar under rain-fed lowland conditions with acceptable accuracy. The model described in this article will be combined with a crop growth model to improve regional yield estimates for rain-fed lowland rice.  相似文献   

10.
南平市推广水稻机插的效益分析与栽培技术   总被引:1,自引:0,他引:1  
文章从物化成本、用工量、劳动强度、产量等方面分析了水稻机插的效益,并针对机插秧苗素质不高,整地质量达不到要求,缺丛率偏高,双晚生育期偏长,不利安全齐穗等问题,提出具体的栽培技术措施.  相似文献   

11.
淹涝胁迫对杂交中稻生长特性及产量形成的影响   总被引:1,自引:0,他引:1  
以近年审定的20个杂交中稻品种为材料,研究了分蘖期和抽穗期淹涝胁迫对杂交中稻的某些生理指标、生长发育、产量及干物质生产的影响。结果表明:(1)淹没胁迫对杂交中稻的生育期有显著影响。分蘖期受淹没胁迫,头季稻和再生稻的抽穗期分别平均延长了3.25 d和3.95 d,成熟期分别平均延长了1.85 d和2.75 d;而抽穗期受淹没胁迫,成熟期会提前,平均提前1.60 d,且品种间差异较大。(2)淹没胁迫对杂交中稻的产量有显著影响。与对照相比,分蘖期受淹没胁迫,分蘖期叶干重、有效穗数、每穗粒数降低,使其平均减产59.0%;齐穗期受淹没胁迫,每穗粒数和结实率显著降低,使其平均减产57.6%。(3)分蘖期受淹没48 h后,不宜割苗蓄留再生稻,应以加强田间管理保留头季稻为主,耐淹性较强的品种有川谷优6684、冈优169和乐优198;抽穗期受淹没48 h后,则以割苗蓄留再生稻较佳,其中冈优169、内5优317、蓉优22和川谷优6684的产量较高。(4)分蘖期和抽穗期耐淹组合间没有相关性,生产上应分别在各时期筛选相应耐淹能力较强的品种。  相似文献   

12.
以南方红壤区双季稻-紫云英为研究对象,利用静态箱-气相色谱法分别分析包括绿肥和稻草等秸秆还田条件下不同水分管理对稻田CH4和N2O排放、水稻产量以及综合温室效应(GWP)的影响。试验设持续淹水(F)、中期烤田(F-D-F)和间歇灌溉(F-D-F-M)处理。结果表明,秸秆还田条件下双季稻田周年CH4排放量介于208.3kg/hm2(F-D-F-M处理)和678.2kg/hm2(F处理)之间,其中,晚稻生长季占周年CH4排放量的60.6%~71.7%。F处理周年CH4排放量显著高于F-D-F和F-D-F-M处理(P0.05)。秸秆还田条件下双季稻田周年N2O排放量为4.75~8.19kg/hm2。与F处理相比,F-D-F-M处理周年N2O排放通量显著增加(60.9%);而F和F-D-F处理之间没有显著差异。早稻和晚稻各处理产量分别为7.76~8.02t/hm2和7.22~8.69t/hm2。秸秆还田条件下,双季稻单位面积GWP和单位产量GWP分别为7648.8~18471.8kg/hm2和0.48~1.12 kg/kg,其中F-D-F和F-D-F-M处理分别显著低于F处理(P0.05)。因此,在秸秆还田条件下采用中期烤田和间歇灌溉替代持续淹水,可以同步实现双季稻高产和减轻农业生产对气候的潜在影响。  相似文献   

13.
《Crop Protection》1999,18(7):451-461
A dynamic model of the effect of rotation and crop management on the frequency of plants infected by eyespot (anamorph Pseudocercosporella herpotrichoides, teleomorph Tapesia yallundae) in a field is proposed and its parameters are estimated on a series of experiments in France during two years. A first equation estimates disease frequency as a function of thermal time and of two parameters associated to the primary (from infectious crop residues) and secondary (from living diseased plants) infection cycles. Two other equations are proposed to estimate the values of the two infection cycle parameters as a function of macro-environment and cropping system; interactions between cultivation techniques were integrated using multiplicative equations. The primary infection cycle parameter depended on crop rotation, soil tillage, sowing date, tiller number per plant and available nitrogen. The secondary infection cycle parameter depended on tiller number per plant. The macro-environment effect on the two parameters is consistent with epidemiological models. The proposed model allows to choose those cropping systems that minimise disease risk for a given set of environmental and technical constraints.  相似文献   

14.
为探究南方稻区优质晚粳稻适宜的断水及收获时期,2014~2015年以常规粳稻镇稻11号及籼粳杂交稻甬优2640为材料,探讨了不同断水时间(抽穗后28、35、42、49 d)、不同收获时期(抽穗后35、40、45、50、55 d)对晚粳稻籽粒充实度、产量及品质的影响。结果表明:在本试验条件下,每延迟1 d断水,镇稻11号及甬优2640产量分别增加21~23 kg/hm^2及31~35 kg/hm^2;每延迟1 d收获,两个品种产量分别增加63~66 kg/hm^2及102~104kg/hm^2。断水(或收获)时期延迟,晚粳稻出糙率、精米率及整精米率增加,垩白粒率及垩白度降低,胶稠度及直链淀粉含量增加。抽穗后42~49 d断水或抽穗后50~55 d收获,晚粳稻产量及千粒重差异均不显著,稻米品质也差异不显著。可见,在江西中部稻区,晚粳稻抽穗后42~49 d断水及抽穗后50~55 d收获较适宜。  相似文献   

15.
Although Cambodia might have achieved self-sufficiency and an exported surplus in rice production,its rice-based farming systems are widely associated with low productivity,low farmer income and rural poverty.The study is based on a questionnaire village survey in 14 communes containing 97 villages of Kampong Chhnang Province from March to June,2011.It analyzes the prevailing rice-based cropping systems and evaluates options for their improvement.Differences in cropping systems depend on the distance from the Tonle Sap water bodies.At distances greater than 10 km,transplanted wet-season rice cropping system with low productivity of about 1.6 t/hm 2 prevails.This deficiency can be primarily attributed to soils with high coarse sand fractions and low pH (< 4.0),use of ’late’ cultivars,and exclusive use of self-propagated seeds.To improve this cropping system,commercial ’medium’ cultivars help prevent crop failure by shortening the cultivation period by one month and complementation of wet-season rice with non-rice crops should be expanded.Areas adjacent (≤ 1 km) to the water bodies become inundated for up to seven months between July until January of each year.In this area,soils contain more fine sand,silt and clay,and their pH is higher (> 4.0).Farmers predominantly cultivate dry-season recession rice between January and April.Seventy-nine percent of the area is sown directly and harvested by combines.Adoption ratio of commercial rice seeds is 59% and yields average 3.2 t/hm 2.Introduction of the second dry-season rice between April and July may double annual yields in this rice cropping system.Besides upgrading other cultivation technologies,using seeds from commercial sources will improve yield and rice quality.Along with rice,farmers grow non-rice crops at different intensities ranging from single annual crops to intensive sequences at low yields.  相似文献   

16.
以超级晚稻H优518为试验材料,进行播期和秧龄的双因素试验。结果表明,该品种可在同生态区域作双晚机插,最迟安全播种期在7月1日前后,秧龄15~20 d移栽,可在武汉市"寒露风"的常年出现日期9月18日前后安全齐穗;播、插期越早,安全性越高,丰产性越好,最高单产可达723.4 kg/667 m~2。  相似文献   

17.
Climate change will have significant impacts on the rain-fed rice production ecosystem, and particularly on the ecosystem’s hydrology and water resources. Under rain-fed lowland conditions, substantial variations among fields in grain yield are commonly observed, but a method that can account for field-scale yield variability to produce regional-scale yield estimates is lacking, thereby limiting our ability to predict future rice production under changing climate and variable water resources. In this study, we developed a model for estimating regional yields of rain-fed lowland rice in Northeast Thailand, by combining a simple crop model with a crop calendar model. The crop model incorporates the effects of two important resources (water and nitrogen) on crop growth. The biomass accumulation is driven by water use, whereas the nitrogen supply determines canopy development and thereby constrains crop water use. Accounting for the wide range of planting dates and the strong photoperiod-sensitive characteristics of rice varieties through the calendar model is an essential component in determining regional yield estimates. The present model does not account for the effects of mid-season drought or flooding, but was nonetheless able to explain the spatial and temporal yield variations at the province level for the past 25 years. Thus, it can be used as a prototype for simulating regional yields of rain-fed lowland rice.  相似文献   

18.
叶面喷施亚硒酸钠对再生稻产量及品质的影响   总被引:3,自引:0,他引:3  
【目的】以叶面喷施的形式研究硒对再生稻产量及品质的影响,旨在为再生稻优质、高产栽培技术提供依据。【方法】试验于2016年在湖北省洪湖市沙口镇进行,以丰两优香1号为试验材料,Na_2SeO_3为供硒源;设置0、5.625和11.250 g/hm~2三个硒肥施用量,始穗期、齐穗期和始+齐穗期三个施硒时期进行叶面喷施。【结果】叶面喷施Na_2SeO_3的处理再生稻产量均高于对照组,始穗期喷施Na_2SeO_3处理的再生稻产量与对照相比虽然有提升但并不显著;齐穗期施用5.625 g/hm~2、11.250 g/hm~2 Na_2SeO_3处理分别增产2.59%和5.50%,始穗期+齐穗期施用5.625 g/hm~2、11.250 g/hm~2 Na_2SeO_3处理分别增产4.83%和7.08%;始穗期与齐穗期均喷施11.250 g/hm~2 Na_2SeO_3处理产量最高,为5533 kg/hm~2,叶面施用Na_2SeO_3能增加再生稻每穗粒数、实粒数和结实率。齐穗期施用11.250g/hm~2 Na_2SeO_3的再生稻稻米整精米率最高,且显著高于对照组,最高值为61.37%;齐穗期施用11.250 g/hm~2Na_2SeO_3的再生稻稻米垩白粒率最低,且显著低对照组,最低值为9.37%。【结论】研究表明,施用Na_2SeO_3能提升再生稻产量,改善再生稻米品质,提升再生稻整精米率,降低垩白率。始穗期与齐穗期均喷施11.250 g/hm~2Na_2SeO_3再生稻产量达到最高;齐穗期施用11.250 g/hm~2 Na_2SeO_3再生稻品质最优。  相似文献   

19.
水稻不同生育阶段营养条件与抽穗期的关系   总被引:5,自引:0,他引:5  
通过2 a多点试验,研究了秧苗生长状态、本田营养条件(密度、肥料)及不同生育阶段营养条件变化对水稻抽穗期的影响.结果表明,移栽密度较大,或施肥较足,或秧苗生长状态较好,均能提早抽穗,其效应大小取决于营养环境的变化程度,秧苗期比本田期的效应更大.不同生育阶段营养条件的变化对抽穗期的影响不同,叶龄指数45%左右是水稻生长发育的一个转折期,在此之前抽穗期对营养条件的反应更敏感,且促进生长与促进发育一致,此后则对营养的敏感性降低,且促进生长不一定能促进发育,有时反而推迟发育.认为将感营养性(受营养生态影响而改变发育速度的特性)与感温性、感光性、基本营养生长期并列("三性一期")描述水稻的生育特性更为合理,制种中更应重视亲本的感营养性.  相似文献   

20.
鄂北双季花生高产栽培技术初探   总被引:1,自引:1,他引:0  
一年内连续两次种植花生是鄂北地区花生种植方式的一项重要改革。通过三年的试验,研究了在鄂北条件下双季连作花生栽培的良种选用、播种期、种植密度和管理措施等关键栽培技术,结果表明以早熟高产的中花4号等品种,第一季地膜覆盖于3月下旬播种,第二季在8月初露地播种并适当增加种植密度,能够获得双季花生7500kg/hm2以上的产量。  相似文献   

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