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以覆盖黑龙江省三个积温带的123个水稻品种(品系)为试材,将6月30日-7月29日每10天为1段分3个时段对水稻进行低温处理,以研究冷害发生规律。结果发现,水稻在6月30日-7月19日受低温易发生延迟型冷害,7月10日-7月19日受低温易发生障碍型冷害,证实了低温对水稻冷害的时段效应;第一积温带水稻在7月10日-7月19日受低温易发生延迟型冷害,第一积温带水稻在6月30日-7月9日受低温易发生障碍型冷害,第二、三积温带水稻在6月30日-7月19日受低温易发生延迟型冷害,第二、三积温带水稻在7月10日-7月19日受低温易发生障碍型冷害,体现了水稻应对低温的生态区效应。这对黑龙江省抗寒水稻品种的选育以及抗寒措施的提出具有指导意义。 相似文献
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根据田间调查资料,从品种选用不合理、育秧技术粗糙、插秧期拖后、障碍性冷害等八个方面分析了2006年尚志市水稻减产原因。依据当地地理、气候等条件,提出了选择优质、高产、抗逆品种;坚持标准化育苗,适时抢早;进行测土配方施肥;及时防治病虫草害等一系列措施。 相似文献
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根据田间调查资料,从品种选用不合理、育秧技术粗糙、插秧期拖后、障碍性冷害等八个方面分析了2006年尚志市水稻减产原因。依据当地地理、气候等条件,提出了选择优质、高产、抗逆品种;坚持标准化育苗,适时抢早;进行测土配方施肥;及时防治病虫草害等一系列措施。 相似文献
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Takemasa Koumoto Naoko Saito Naohiro Aoki Toshiki Iwasaki Shigenao Kawai Shuji Yokoi 《Plant Production Science》2016,19(4):497-507
We tested whether exposing rice plants to abiotic stress (salt or shade) during vegetative growth affects the chilling tolerance of reproductive organs, which is one of the most important traits for rice growing in a cool climate; we used two rice cultivars with different tolerance in two growing seasons. We divided the vegetative growth into three phases to clarify the most sensitive period: 7–22 days after transplanting (DAT), 23–38 DAT and 39–54 DAT. Chilling tolerance of the pre-stressed plants was based on the male sterility induced by low temperatures. Shade and salt stress during all three vegetative growth phases significantly reduced stomatal conductance. Shade decreased the specific leaf weight and the leaf sugar and starch contents, but salt had no significant effect, despite causing leaf damage. Low temperatures during the reproductive stage induced spikelet sterility in all plants, but the magnitude was greater in the salt- and shade-stressed plants of both cultivars, especially those stressed late during vegetative growth. The increased spikelet sterility caused by chilling was closely related to the reduction of the total spikelet number per panicle. This is the first study to show that salt and low light stress during vegetative growth increased the susceptibility of rice plants to chilling damage during panicle development. 相似文献
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Dipanwita Haldar Rahul Nigam C. Patnaik Sujay Dutta Bimal Bhattacharya 《Paddy and Water Environment》2016,14(4):451-461
Assessing the nature and extent of damage due to natural calamities remains one of the thrust areas in monitoring resource inventory through remote sensing. The effect of the cyclone Phailin and the post-incessant rains during second fortnight of October 2013 on coastal Odisha was studied in terms of rice area flooded, submerged and damaged. Multi-temporal SAR data were analysed to obtain the rice mask, and from this rice mask, the flood affected rice area was determined. Taluka-wise and district-wise crop loss proportion was estimated, and the overall production loss has been estimated. SAR data aided in delineation of flooded regions, while AWiFS NDVI data of subsequent dates showed both continued inundation and crop vigour status post-flood time period. The ground truth indicated that a major portion of the inundated region was not rice but was typha grasses and harvested rice field which should not be accounted as damage to rice crop. The damage on crop yield was difficult to assess; however, the inundation of the crop at panicle initiation and flowering would have impact on grain filling (results in chaffiness) and was considered as completely damaged. Most of the current inundated rice regions fall in this category. It was estimated that a total of 0.167 million hectares and 0.37 million tons of rice crop was lost in the cyclone and floods. The district-level percentage area of rice flooded was communicated to State Remote Sensing Centre in four days timeframe. The overall accuracy obtained for the validation of the ground truth sites was 91.5 %. 相似文献
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杂交稻新组合再生稻头季及再生季源库特征分析 总被引：14，自引：0，他引：14
以6个两系杂交组合和2个三系杂交组合为材料，比较研究了杂交稻头季与再生季的源库特性和再生稻产量形成的源库关系。结果表明：(1)再生季LAI为头季的1/3左右，再生稻单茎叶面积约为头季稻的1/7~1/3，头季总库容约为再生季的1.5倍，再生稻粒叶比约为头季稻的1.5~2倍；(2)头季稻较大的粒叶比对高产有利；头季稻成熟期LAI较大、粒叶比较小、成熟期单茎鞘干质量较大、茎鞘物质输出率高，有利于再生稻的高产；(3)再生季齐穗期LAI与产量成显著正相关；对高节位再生稻而言，齐穗期单茎叶面积与单茎产量呈极显著正相关，粒叶比与结实率呈负相关、与产量呈极显著负相关。再生稻，特别是高节位再生稻，其源库关系属增源增产型；(4)陆18S/53159、康两优2054、培矮64S/E32和培两优500再生季产量较高，均在5200 kg/hm2以上。综合考虑再生季产量与两季总产，在2002年气候条件下，长沙地区最适于再生栽培的杂交稻是培矮64S/E32，其次是康两优2054和T98A/259。 相似文献
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从细胞膜系与植物抗冷性,可溶性糖、蛋白质与植物抗冷性,脯氨酸及其它氨基酸与植物的抗冷性,低温下冷害指数、电导率、原生质膜透性与植物的抗冷性等方面综述了水稻低温冷害生理研究进展,为今后的水稻冷害研究提供科学依据。 相似文献
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Deficit irrigation management for rice using crop growth simulation model in an optimization framework 总被引：3，自引：2，他引：1
Optimization of irrigation water is an important issue in agricultural production for maximizing the return from the limited
water availability. The current study proposes a simulation–optimization framework for developing optimal irrigation schedules
for rice crop (Oryza sativa) under water deficit conditions. The framework utilizes a rice crop growth simulation model to identify the critical periods
of growth that are highly sensitive to the reduction in final crop yield, and a genetic algorithm based optimizer develops
the optimal water allocations during the crop growing period. The model ORYZA2000, which is employed as the crop growth simulation
model, is calibrated and validated using field experimental data prior to incorporating in the proposed framework. The proposed
framework was applied to a real world case study of a command area in southern India, and it was found that significant improvement
in total yield can be achieved by the model compared to other water saving irrigation methods. The results of the study were
highly encouraging and suggest that by employing a calibrated crop growth model combined with an optimization algorithm can
lead to achieve maximum water use efficiency. 相似文献
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Crop management plays an important role in the transition from a deepwater rice to a flooded rice production system but information about optimum management strategies are currently lacking. The goal of this study was to determine the effect of planting date and variety on flooded rice production in the deepwater area of Thailand. Two experiments were conducted at the Bang Taen His Majesty Private Development Project in 2009 and 2010 to represent conditions prior to flooding (early rainy season) and after flooding (dry season). The early rainy season crop covered the period from May to October 2009, while the dry season crop covered the period from November 2009 to April 2010. The experimental design was a split plot with four main plots and three sub plots replicated four times. The treatments for the main plot were various planting dates, while the treatments for the sub plots were rice varieties. The dates of the critical developmental phases of rice were recorded and biomass was sampled during the growing period. The collected data were statistically analyzed using ANOVA and treatment means were compared to identify the appropriate plating date and the best variety for the area. The highest average yield was obtained for variety PSL2 across transplanting dates from June 19 to July 23, with an average yield of 3898 kg ha−1. The dry season crop showed that both biomass and yield were affected by the interaction between planting date and variety. The highest yield was obtained for variety PTT1 transplanted on November 9. The research showed that the variety PSL2 is the most suitable variety for early rainy season production with a transplanting date ranging from June 19 to July 23, while the variety PTT1 planted on November 9 was the best management practice for the dry season crop. However, a high yielding flooded rice variety that has a short growth duration is still needed for this area. 相似文献
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以黑龙江省30份主栽水稻品种或品系为试材,在孕穗期设置17℃冷水灌溉处理(20d),以常规栽培管理为对照,分析冷水胁迫对水稻干物质生产的影响。结果表明,冷水胁迫导致所有试材每穴实粒数、结实率、千粒重和产量下降,并根据相对结实率将试材耐冷性分为1、3、5、7和9级,以7和9级最多,1级最少,分别占总材料的30%和10%。在冷水处理下,全部材料抽穗期至成熟期干物质积累量及比例、群体生长率、净同化率、粒叶比、收获指数、叶面积指数、剑叶叶基角、剑叶和倒2叶与倒3叶披垂度均下降,但高效叶面积率增加。相关分析表明,冷水处理的相对结实率与收获指数(r=0.96**)、产量(r=0.91**)、粒叶比(r=0.84**)和干物质积累量(r=0.48**)的冷水反应指数(CRI)呈极显著正相关,与群体生长率(r=0.44*)、净同化率(r=0.44*)和干物质积累比例(r=0.43*)的CRI显著正相关。综上,孕穗期冷水胁迫对水稻干物质生产的影响在品种间存在很大差异,在冷水胁迫下耐冷性极强品种(系)干物质积累量及比例、群体生长率、净同化率、粒叶比和收获指数对冷水反应迟钝,这是耐冷性极强品种(系)保持较高产量的重要形态特征和生理原因。 相似文献
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浙江省籼粳杂交晚稻品种发展与展望 总被引：2，自引：0，他引：2
2005年,浙江省审定通过首个籼粳亚种间强杂种优势品种甬优6号。针对甬优6号存在的生育期偏长、植株高大、稻曲病偏重易发等问题,育种单位创新了育种理念和技术,品种管理部门在技术推广上有针对性地加强试验和示范,促进了浙江省籼粳杂交晚稻品种选育和审定推广,至2015年已审定品种21个,累计推广面积110.17万hm~2,其中2015年达21.12万hm~2,占全省杂交水稻种植面积的60%以上;开展籼粳杂交晚稻品种选育的科研单位和种业企业增加到14家,并更加关注适应不同推广区域、不同耕作制度的品种选育,同时施肥、用药等技术也更加精准易用。 相似文献
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【目的】为了探究低温冷害胁迫后水分/湿度对水稻幼苗根系活力和水分运输等的影响,【方法】以具有低温耐性差异的嘉籼7号和辐8329两个水稻品种为研究材料进行低温胁迫处理后,在进行实验Ⅰ（不同湿度梯度,正常温度培养条件下）和实验Ⅱ（快速回温处理实验,以正常温度恢复为对照）。【结果】实验Ⅰ结果表明,与较低湿度（30%）相比,较高的湿度（60%和90%）可以提高根系活力,有效保证水稻幼苗的存活率并缓解其遭受的低温冷害。水孔蛋白基因OsPIP2;5和OsPIP2;6的表达水平与根系活力密切相关,对水稻的抗寒和低温耐性具有显著的调控作用。实验Ⅱ结果表明,与对照组（CK）相比,快速回温处理后水稻幼苗的含水量和根系活力显著降低;且正常自然恢复状态下,两个水稻品种的存活率明显高于快速回温组幼苗。【结论】低温胁迫显著影响水稻幼苗的生长发育过程。较高的湿度环境有助于缓解幼苗的低温冷害损伤,保证存活率。同时,低温胁迫后的外界环境湿度对水稻幼苗的含水量、根系活力和水孔蛋白相关基因表达有显著影响,其中OsPIP2;5和OsPIP2;6的表达水平与根系活力正相关,在水稻幼苗抵御外界低温冷害过程中起重要作用。因此,与低温胁迫后田间大量灌溉相比,正常温度下土壤缓慢的温度上升对幼苗的根系活力影响较小,有助于其在低温冷害后恢复生命活动。 相似文献
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Shahbaz Khan 《Paddy and Water Environment》2007,5(3):143-152
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
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Characterizing and Estimating Fungal Disease Severity of Rice Brown Spot with Hyperspectral Reflectance Data 总被引：1，自引：0，他引：1
Large-scale farming of agriculture crops requires real-time detection of disease for field pest management.Hyperspectral remote sensing data generally have high spectral resolution, which could be very useful for detecting disease stress in green vegetation at the leaf and canopy levels. In this study, hyperspectral reflectances of rice in the laboratory and field were measured to characterize the spectral regions and wavebands, which were the most sensitive to rice brown spot infected by Bipolaris oryzae (Helminthosporium oryzae Breda. de Hann). Leaf reflectance increased at the ranges of 450 to 500 nm and 630 to 680 nm with the increasing percentage of infected leaf surface, and decreased at the ranges of 520 to 580 nm, 760 to 790 nm, 1550 to 1750 nm, and 2080 to 2350 nm with the increasing percentage of infected leaf surface respectively. The sensitivity analysis and derivative technique were used to select the sensitive wavebands for the detection of rice brown spot infected by B. oryzae. Ratios of rice leaf reflectance were evaluated as indicators of brown spot. R669/R746 (the reflectance at 669 nm divided by the reflectance at 746 nm, the following ratios may be deduced by analogy), R702/R718, R692/R530, R692/R732, R535/R746, R521/R718, and R569/R718 increased significantly as the incidence of rice brown spot increased regardless of whether it's at the leaf or canopy level. R702/R718, R692/R530, R692/R732 were the best three ratios for estimating the disease severity of rice brown spot at the leaf and canopy levels. This result not only confirms the capability of hyperspectral remote sensing data in characterizing crop disease for precision pest management in the real world, but also testifies that the ratios of crop reflectance is a useful method to estimate crop disease severity. 相似文献