早稻受涝后应看灾情合理补救

<正>6~7月是南方地区的多雨季节,局部地区有可能下暴雨或大暴雨,引起洪涝灾害,尤其是部分低洼稻田受淹的可能性更大,早稻、中稻、晚稻秧田均有可能遭受灭顶之灾。受淹稻田稻株根系受损,甚至出现大量死苗,应根据早稻受淹具体程度及生长情况,采取相应的补救措施。一、受淹早稻的特征早稻在不同生育期的耐涝能力不同,受     

水稻涝害的补救措施

<正>水稻耐涝性较强,一般洪涝期间淹没1昼夜,稻苗生育基本不受影响;淹没2~3昼夜,只要排水后补救措施跟得上,产量也不会受到大的影响,淹没3昼夜以上对产量有较大影响,淹没7昼夜以上,影响极大,基本绝收。在受淹3~7昼夜范围内,受淹时间每增加1昼夜,单产会下降10%左右。灾后应根据水稻生育期、受害程度、生产季节采取相应补救措施。水稻分蘖期受淹3~5天排水后,若仍有     

杂交水稻中后期洪涝淹没与产量损失的关系

以4个杂交中稻品种为材料, 采用桶栽方法在模拟洪水和实地洪涝条件下, 研究了在水稻不同生育时期模拟洪水淹没的深度、时间对产量损失度的影响。结果表明, 淹没对产量损失度的影响为抽穗期>孕穗期>乳熟期, 淹顶>淹没植株2/3。洪水淹没下结实率和千粒重与淹没时间呈极显著负相关。在淹没植株2/3处理中, 孕穗期、抽穗期、乳熟期淹没100 h, 产量分别损失50%、60%、12%左右; 而淹顶处理100 h的产量损失度, 在孕穗期、抽穗期达100%, 在乳熟期不到25%。预测洪涝产量损失度分别达40%、60%和80%时相应的淹没时间, 建立了根据不同淹没时期和淹没深度的产量损失度与淹没时间关系模型, 决定系数为0.6038~0.9868。孕穗期、抽穗期和乳熟期分别在洪涝淹没56.3 h情况下, 产量损失度实测值与预测值误差为3.63~6.81个百分点, 可作为洪灾发生后评估水稻产量损失度的参考依据。     

洪涝过后须防水稻心腐病

<正>水稻心腐病又名细菌性褐条病,是一种假单胞杆菌引起的水稻病害,因水稻感病后烂心而得名,在长江流域稻区局部地区流行。近年来该病的危害有逐年加重趋势,其原因主要是早稻和中稻生长季节常常会遇到规律性的暴雨,稻苗受淹和遭洪涝侵袭后,容易诱发该病的大流行,影响水稻的正常生长,并造成减产。今年暴雨天气多,值得引起重视。     

受灾水稻“早翻晚”技术

正6月下旬以来,安徽省各地遭受持续暴雨影响,部分地势较低的低洼圩田的秧苗淹水深、淹没时间长,秧苗受伤严重甚至死亡。笔者认为,水稻淹没秧苗生长点、淹水时间超过2天、叶片腐烂的田块最好改补种。如果仍然种植水稻,建议改种早稻,实行"早翻晚"栽培,其栽培技术要点如下:选择合适早稻品种。品种的选择要与淹水田退水时间相匹配,凡是7月上旬能够退水的,可选择早稻品种,实行     

不同播期对超级稻早稻产量结构的影响

为摸清超级稻种植气候生态适应性,合理利用气候资源、合理安排播种期,减轻农业气象灾害对益阳地区双季超级早稻生产的影响,以‘株两优819’为试验材料,在益阳市赫山区连续2年进行分期播种试验,分析不同播期产量结构差异性,分析产量与气候条件之间的关联。结果表明:连续2年均以第三播期产量最高,不同气候年景下,超级稻产量年际变幅增加;超级稻双季早稻全生育期随着播期延后而缩短,不同播期超级稻双季早稻的差异主要体现在生殖生长阶段;总粒数与拔节至孕穗期间日平均气温≤22℃的天数呈负相关;乳熟至成熟期间日最高气温≥35℃持续日数超过5天可作为高温对其造成明显影响的临界指标。益阳地区超级稻双季早稻适宜播种时间为3月下旬后期至4月上旬。     

不同秧龄对早稻经济性状及产量的影响

<正>福建省福清市水稻种植以早、中、晚稻为主。随着社会经济不断发展及劳动力转移,目前福清市大部分土地已流转集约经营,种植大户大多采用"早稻—再生稻—蔬菜"和"中稻—蔬菜—蔬菜"的耕作模式随之产生一些农业企业与种植大户对育秧秧龄掌握不准确、移栽期偏迟而造成对水稻经济性状及产量的影响,为明确不同秧龄对早稻生产的影响,结合福清市早中稻的生长特点开展不同秧龄移栽的比较试验。     

涝灾棉花田间管理措施

2006年6月29日到7月4日,江苏省阜宁县境内连降暴雨,累计降雨量达418mm,流域性河流水位超警戒水位1.21m,超历史最高水位0.05m。雨量居20世纪80年代以来之首,涝灾重于2003年。对正处于现蕾开花期棉花造成了极大影响。不少棉田长期积水,导致棉花生理机能衰退,叶片受伤,根系受损,出现烂根、黑根和死苗。综合1991年和2003年棉花涝后抢管夺高产的经验,在田间管理上针对不同涝灾特点分类指导。因苗、因田制宜,充分利用棉花补偿能力强,恢复生产快的特点,加强田间管理。1受淹棉田(整株淹没)1.1排水先鉴定棉花植株生死。连续淹没5d以上,退水前主茎表皮呈褐色或顶心茎叶糜烂的,退水后棉株倒伏……     

气象条件对水稻生产影响研究

为了研究气象条件对水稻生产的影响,为当地水稻的种植生产提供依据,对安徽南陵2005—2014年早稻、中稻和一季晚稻、双季晚稻全生育期的主要气象因子进行分析评价,研究其对各类水稻气象产量的影响,并定量计算出各气象因子与该三类水稻气象产量的相关系数。结果发现：水稻气象产量具有明显的年际变化,早稻和双季晚稻整体呈上升趋势,中稻和一季晚稻基本持平,略有下降。对比分析和相关性显示,早稻气象产量与降水量和蒸发量相关性较大,且与降水量和蒸发量分别呈负相关和正相关;中稻和一季晚稻受温度、蒸发量和降水量影响显著,与蒸发量相关性最大,并且与降水量成正比,与温度、蒸发和日照时数成反比;双季晚稻与各气象因子的相关性较前两种水稻偏小。该研究获得了南陵不同气象因子对水稻生长的影响程度,为今后水稻种植合理避开气象灾害打下基础。     

当前“两迁”害虫发生动态及趋势预测

<正>当前,南方稻区早稻已基本收割,中稻大部处于抽穗至扬花期,晚稻大部处于移栽至分蘖拔节期。由于近期强对流天气活动频繁,"两迁"害虫大量转迁至华南、西南和江南中稻以及长江中下游单季稻危害一、当前发生情况稻飞虱近期,受强对流天气影响,华南、江南和长江中下游稻区灯下虫量峰次增多,虫量增多,发生态势加重。     

淹涝胁迫条件对水稻形态的试验研究初报

为分析不同品种早稻对水淹胁迫的响应,于2012年3—7月分别对不同品种水稻的分蘖期、抽穗扬花期耐淹能力及不同淹涝强度对一些农艺性状的影响进行了研究。结果表明：分蘖期不同品种籼稻在不同的淹涝强度处理间的株高变化结果不一。不同淹水处理小区出现主茎穗和分蘖穗发育进程不一致,生育期延长天数与淹水天数之间呈现极显著的正相关关系。因为‘湘早籼24’植株相对比较矮,受钻心虫危害比较严重。钻心虫发生面积和淹水强度之间呈现极显著的正相关关系。淹水处理造成水稻产量降低,试验结果表明同一品种,产量降幅随淹水时间延长而加大。     

The Effect of Mulching,Tillage and Rotation on Yield in Non‐flooded Compared with Flooded Rice Production

Non‐flooded rice cultivation has been proven to be an effective measure to reduce water consumption in drought areas of Southeast China. However, rice cultivation under non‐flooded conditions leads to less stable productivity and lower grain yield. The objectives of this study were (1) to compare crop performance and yields among flooded and non‐flooded rice over several seasons, (2) to identify the yield performed in non‐flooded rice systems over seasons and whether the options which included no‐tillage, straw mulching and wet‐dry rotation system can narrow the grain yield gap between non‐flooded and traditional flooded condition. The results showed the difference between flooded rice (F) and non‐flooded rice (NF) with straw mulching was much lower than the difference between F and NF without straw mulching. Within late seasons, the difference of aboveground total biomass between non‐flooded rice without mulching and flooded rice gradually widened as the number of cropping seasons increased. Compared with the non‐flooded rice without mulching, straw mulching can reduce the decline of aboveground total biomass and grain yield. The yield difference between F and NF treatments became smaller in no‐tillage plots than complete tillage plots. It suggested that no‐tillage can keep the crop production more stable. In comparison with continuously non‐flooded cultivation, our study indicated that the wet‐dry rotation system can reduce the yield decline under non‐flooded condition.     

抽穗扬花期淹涝胁迫对杂交稻的影响

为了研究淹涝胁迫环境下,抽穗扬花期杂交稻形态特征及产量结构的变化,以杂交晚稻‘湘丰优103’为供试材料,在抽穗扬花期设计不同淹水深度及淹水时间的淹涝胁迫试验,通过测定淹水前后水稻绿叶数、气生根、倒伏状况、产量构成等因素的变化,分析杂交稻对淹涝胁迫环境的敏感性。结果表明,相同淹水深度,淹水时间与绿叶数变化量均呈极显著负相关关系。产生气生根的茎的比率与淹水深度呈负相关关系,与淹水时间呈正相关关系。抽穗扬花期发生的倒伏为茎倒伏,同一淹水深度,水稻植株的断茎百分率和淹涝时间呈极显著正相关关系。产量结构方面,抽穗扬花期对淹涝胁迫环境非常敏感,全淹5天以上,几乎绝收,全淹3天,结实率仅有28粒,比对照少74粒,产量非常低。通过研究淹涝胁迫环境下抽穗扬花期的杂交稻形态特征及产量结构的变化,明确了不同淹涝环境下抽穗扬花期杂交稻形态变化和产量因子的变化,了解了杂交稻对淹涝胁迫环境的适应机制和敏感性,为进行洪涝灾害致灾能力、强度的鉴定提供形态学和产量结构的数据基础。     

不同水分管理条件下秸秆还田方式对作物养分吸收、产量及土壤培肥的影响

盆栽试验结果表明,常规淹水和无水层栽培,秸秆还田的水稻产量提高,油菜秸秆和小麦秸秆处理之间差异不显著,秸秆不同利用方式以覆盖效果较好。秸秆还田处理的后茬油菜产量比不施秸秆的提高1.8%～9.3%。对氮磷钾吸收的影响,常规淹水多于无水层栽培,但秸秆还田能促进氮磷钾的吸收利用。无水层栽培比常规淹水栽培的土壤有机质等养分提高,说明无水层栽培条件下更利于还田秸秆的养分释放和土壤对养分的保持。     

砷胁迫下水磷耦合对不同磷效率水稻农艺性状及精米砷含量的影响

为探索缓解水稻砷毒害的农艺措施,选用耐低磷水稻99011和低磷敏感水稻99012,研究水分管理、磷用量及其交互作用对不同砷浓度酸性土壤上水稻生长发育、产量及稻米砷含量的影响。结果表明,节水灌溉(干湿交替)和增施磷肥都明显促进水稻生长(包括分蘖数、总穗数、有效穗、根系干重、生物量)和产量形成,缓解砷胁迫对水稻生长和产量的不利影响,且水、磷交互作用也表现出明显的正效应。50 mg kg^-1砷处理时,节水灌溉显著降低精米砷含量,而增施磷肥提高了精米砷含量,水、磷交互效应明显比水分管理效应差,但比磷肥效应好得多;100 mg kg^-1砷处理时,节水灌溉和增施磷肥都明显降低精米中的砷含量,且二者交互表现出正效应。土壤加砷后,相同处理的生物学性状均为耐低磷水稻明显大于磷敏感水稻,而精米砷含量则为耐低磷水稻显著低于磷敏感水稻。研究表明,可以根据砷污染程度采取干湿交替水分管理、调节磷用量以及选择吸收磷能力强的耐低磷水稻品种等措施缓解砷污染对水稻生长、产量和品质的不利影响。     

Estimating canopy cover from color digital camera image of rice field

Canopy cover (CC) is a good predictor variable for plant growth parameters such as leaf area index and aboveground biomass. A nondestructive, low-cost, and convenient method is presented for estimating CC using digital camera image analysis. CC was estimated by the ratio of plant pixels to total pixels of digital camera image of rice field. To determine the criteria for segmenting the rice plant from variable soil background, three mosaic images for rice plant, flooded/bare soil, and algae-infested background were prepared from digital camera images that were taken in various field conditions. An image analysis program was developed in Visual Basic to extract red, green, and blue (RGB) features from the mosaic images, calculate RGB-based color indices, and compute the minimum segmentation error for separating rice plant from background. When judged by the segmentation error, modified excessive green index (MEGI) showed the highest potential for segmenting rice plant from flooded/bare soil background, followed by normalized green (g) and excessive green index (EGI). At the threshold MEGI value of 0.03, the segmentation error was the lowest as 0.13%. Any single index considered was not satisfactory in segmenting rice plant from algae-infested background. However, a discriminant function of 1.2553EGI + 0.01735G − 0.01474B was successful in segmenting rice plant from flooded/bare soil and algaeinfested background with segmentation errors of 0.34 and 1.17%, respectively. CC for four rice varieties from tillering to booting stage was estimated based on the threshold value of MEGI and discriminant function and also manually using commercial software. Both estimates of CC showed good relationship of r² = 0.94, suggesting that a digital camera could be used efficiently for measuring the CC of rice field.     

旱种方式对水稻产量与品质的影响

以汕优63为材料,通过稻草覆盖旱种、地膜覆盖旱种和常规水种（对照）比较试验,研究了旱种水稻产量与品质的表现。结果表明,覆草旱种产量与水种稻产量无显著差异,但显著高于覆膜旱种稻的产量。覆草旱种稻米的碾磨品质、外观品质、蒸煮品质和营养品质与水种稻无显著差异,而覆膜旱种稻米的垩白度明显高于水种稻,胶稠度和碱解值则显著低于水种稻。水稻旱种后,淀粉谱的最高黏度和崩解值降低,消减值提高,覆膜旱种尤为明显。旱种稻的地上部干物质积累量减少,根干重增加,物质运转率和收获指数提高,灌浆中后期根系活力下降较快。表明覆草旱种的产量、稻米品质以及物质生产均优于覆膜旱种。对覆草旱种和覆膜旱种在产量和品质形成上的差异进行了讨论。     

Seed priming improves stand establishment and productivity of no till wheat grown after direct seeded aerobic and transplanted flooded rice

No tillage (NT) in wheat (Triticum aestivum L.) offers a pragmatic option for resolving the time and edaphic conflicts in rice (Oryza sativa L.)–wheat cropping system (RWS). However, poor stand establishment is an issue in NT wheat, which adversely affects crop growth, grain yield, and profitability. Therefore, a 2-year field study was conducted to assess the potential role of seed priming in improving the stand establishment, grain yield, water productivity and profitability of NT and plough till (PT) wheat grown after direct seeded aerobic (conservation) and puddled transplanted flooded (conventional) rice-based systems. For seed priming, wheat seeds were soaked in aerated water (hydropriming) or solution of CaCl₂ (ψs −1.25 MPa; osmopriming) for 12 h, and non-primed seeds were used as control. After harvest of rice, grown as direct seeded aerobic and puddled transplanted flooded crop, primed and non-primed wheat seeds were sown following NT and PT. In both years, stand establishment of NT wheat after direct seeded aerobic and puddled transplanted flooded rice was impeded. Nonetheless, seed priming improved the stand establishment which was visible through earliness and better uniformity of seedling emergence. Overall, primed seeds completed 50% emergence in 6.4 days, against 7.8 days taken by non-primed seeds in NT wheat. The highest emergence index (41.7) was recorded in primed seeds versus 32.0 for non-primed seeds. Improved stand establishment enhanced growth, grain yield, water productivity and profitability in NT wheat. In this regard, osmopriming was the most effective, and produced grain yield of 4.5 Mg ha⁻¹ against 3.8 Mg ha⁻¹ for non-primed seeds in NT wheat. Water productivity of the NT wheat grown from osmoprimed seeds was 8.72 kg ha⁻¹ mm⁻¹ while that from non-primed seeds was 7.21 kg ha⁻¹ mm⁻¹. Among the RWSs, the maximum wheat biomass was produced with PT after direct seeded aerobic rice. However, grain yield, water productivity, and profitability were the highest in NT wheat following direct seeded aerobic rice. Wheat yields grown after direct seeded aerobic rice and transplanted flooded rice were 4.4 and 4.2 Mg ha⁻¹ respectively. Planting NT wheat after direct seeded aerobic rice provided the highest system productivity (1.80) than other RWSs. Thus, seed priming is a viable option to improve the stand establishment, grain yield, water productivity and profitability of NT wheat in the RWS. Nonetheless, osmopriming was a better option than hydropriming in this regard.     

Interaction between quinclorac and imidazolinones in the control of resistant Cyperus iria to ALS inhibitors

Journal of Crop Science and Biotechnology - Herbicides belonging to the chemical group imidazolinones and the quinclorac herbicide are important to control weeds in flooded rice. The objective of...