Economics of Residues Incorporation and Phosphorus Application for Direct Seeded Rice and Wheat under Saline Soil

Two-year long field study was conducted using a permanent layout to investigate the economics of crop residues incorporation (2 t&middotha-1) and P application (0, 40, 80 and 120 kg P2O5 ha-1) to directly sowing of rice and wheat crops gown under naturally salt-affected calcareous soil (ECe = 4.59 dS m-1;pHs = 8.38;SAR = 6.57 (mmolc L-1)1/2;CaCO3 = 3.21%;Extractable P = 4.07 mg&middotkg-1;sandy clay loam) at farmers field in district Hafizabad during the year 2012-13. Split plot design (crop residues in main plots and P application in sub plots) was followed with three replications. Agronomic data on growth and yield were collected at the time of each crop maturity. Maximum growth and yield of both the crops were harvested from the plots where P2O5 was applied @ 80 kg&middotha-1 along with crop residues incorporation. On an average of two years, maximum paddy (3.26 t&middotha-1) and wheat grain (3.56 t&middotha-1) yield were produced with P application @ 80 kg P2O5 ha-1 along with crop residues incorporation. Although, the yield harvested with this treatment (80 kg P2O5 ha-1 + crop residues) performed statistically equal to 120 kg P2O5 ha-1 without crop residues incorporation during both the years, however, on an average of two years, grain yield of directly sowing rice and subsequent wheat was significantly superior (22% and 24% respectively) than that of higher P rate (120 kg&middotha-1) without crop residues. Overall, continuous two-year crop residues incorporation further increased (17%) paddy yields during the follow up year of crop harvest. Economic analyses of both the crops were carried out to choose the best treatment with adequate economic benefits as compared to those without crop residue incorporation. Maximum net benefit of Rs = 108,680/- for direct seeded rice and Rs = 99,362/- for wheat grown with 80 kg P2O5 ha-1 application under crop residues incorporation was determined. Among P application treatments without crop residues incorporation, the maximum net benefit (Rs = 75,874/- and Rs = 65,725/-) and highest residual values (49,809 and 39,160) for direct seeded rice and wheat respectively, were obtained with extended P application rate (120 kg P2O5 ha-1) which was not again as much as that of 80 kg P2O5 ha-1 application with crop residues incorporation.

Chemical Weeding in Dry Direct Seeding Fields of Single Cropping Middlelate Rice

Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide（ pretilachlor ＋ bensulfuron-methyl,Yangguo and butachlor）,and the sub-treatment was application method（ soil treatments,seedling treatment and integrated treatment）. The results showed that 80 g pretilachlor ＋ bensulfuron-methyl（ 36% pretilachlor ＋ 4% bensulfuron-methyl） diluted with 50 kg water could be sprayed or 200 g Yangguo（ 23. 9% butachlor ＋ 1. 1% bensulfuron-methyl） mixed with 15 kg sandy soil could be broadcasted per 667 m2 on the sowing day or the second day under moist condition of soil,which could effectively control weeds in dry direct seeding fields of single cropping middle-late rice.

Prevention Effects of Pyrazosulfuron-ethyl·Quinclorac 50% WP on Stem and Leaf of Dry Direct Seeded Rice

[Objective] The aim was to explore the prevention effects of pyrazosul-furon-ethyl·quinclorac 50% WP on stem and leaf of dry direct seeded rice. [Method] Totaling 7 drug doses were set in the test and the effects were observed 5, 10, 15 and 30 d after drug application, with the remained weeds surveyed 15 and 30 d after drug application. [Result] The test showed pyrazosulfuron-ethyl·quinclorac 50%WP was safe to rice as treatment agent of stem and leaf, and rice yield increased dramatical y, with the growth rate in 2.1%-49.3%. After the drug application, the prevention effects on Echinochloa crusgal i, Ludwimlia prostrata, Monochoria vamli-nalis, and Zong grass were 92.2%, 96.6%, 93.5%, and 94.8%, and the effects on fresh weight were 94.8%, 97.1%, 93.3% and 94.9%, respectively. [Conclusion] Pyra-zosulfuron-ethyl·quinclorac 50% WP can be taken as treatment agents of stem and leaf of dry direct seeded rice.

Control Efficiency and Crop Safety of 20% Cyhalofop-butyl WP on Grass Weeds in Direct Seeded Rice Fields

The purpose was to define the control efficiency and safety of 20% cy- halofop-butyl WP on grass weeds in direct seeded rice fields, in order to provide the basis for chemical weeding. This study measured Leptochloa chinensis（L.） Nees, Echinoch/oa crusgalli （L.） Beauv and other gramineous weed control efficiency with four concentrations of 20% cyhalofop-dutyl WP and 100 g/L cyhalofop-dutyl EC in direct seeded rice fields, and analyzed the yield-increasing effect and safety of rice. The results showed that 20% cyhalofop-butyl WP had a good control efficiency on grass weeds such as Leptochloa chinensis（L.） Nees, Echinoch/oa crusgalli（L.） Beauv and other grasses. The effective dosage of 90-150 g/hm2 was over 90.7% on Lep- foch/oa chinensis（L.） Nees and the comprehensive control effect of the grass weeds was above 86.7%, which was basically consistent with 100 g/L cyhalofop-dutyl EC. Furthermore, 20% cyhalofop-dutyl WP was high security for direct seeded rice fields. The yield of rice was increased by 10.18%-11.22% after spraying herbicide. There- fore, 20% of cyhalofop-dutyl WP can be used as a special herbicide for controlling Leptochloa chinensis（L.） Beauv in direct seeded rice fields, and has a good applica- tion prospect.

直播稻播前不同土壤火焰温度条件下杂草种子发芽率试验

杂草的有效控制是降低直播稻稳产风险的重要措施,播前土壤火焰处理是以非化学方法在进行播种前抑制杂草种子萌发的有效手段。为明确土壤火焰处理中温度场对杂草种子发芽率的影响规律,采用数值模拟方法对燃料分流部件中集管结构参数进行了研究,数值模拟和验证试验结果表明,当集管内径d为20 mm、气体输入流量为1.0~3.5 m^(3)/h时,最大流量偏差系数Δη在3.0%以内,支管间气体流量分配较均匀。基于数值模拟结果设计了火焰燃烧装置,研究6种输入流量(1.0~3.5 m^(3)/h)的液化石油气燃料对火焰高度和火焰温度分布的影响,以拖拉机行进速度、燃料输入流量和土壤深度作为试验因素,进行了全因素试验,采用稻田间常见的杂草种子研究温度场对杂草种子发芽率的影响规律。试验结果表明,在常温常压工作环境下,火焰高度和火焰温度最高值均随着燃料输入流量的增大而增大;当拖拉机行进速度为2.36 km/h,燃料输入流量为2.5、3.0、3.5 m^(3)/h时,土壤温度最高值可分别达到92.83、116.58、156.83℃;相比未经火焰处理的对照组,当土壤温度达到92.83℃时,在α=0.05的显著性水平下,千金子、异型莎草种子发芽率显著降低,但马唐、鳢肠种子发芽率受影响不显著,当土壤温度达到116.58℃和156.83℃时,4种杂草种子发芽率均显著降低;当土壤温度达到156.83℃时,马唐、鳢肠、千金子和异型莎草4种杂草种子发芽率分别降低94.82%、87.81%、86.54%和84.05%。田间试验结果表明,土壤火焰处理对稗草、马唐、鳢肠和异型莎草有显著的抑制萌发作用,其相对除草率Y≥80.00%。

稗草对机械穴直播水稻产量的影响及其生理机制

为了给机械穴直播水稻高产栽培和杂草综合治理提供科学依据,以苏粳4699为试验材料,自水稻播种后7 d至成熟分别与光头稗和无芒稗共生,以无杂草的水稻处理为对照,研究机械穴直播条件下稗草对水稻产量的影响及其生理机制。结果表明,与对照相比,水稻与稗草共生后产量显著降低,但处理间存在较大差异。光头稗处理显著降低了水稻的每穗粒数、结实率和千粒重,造成水稻减产13.0%,而无芒稗处理的水稻减产55.2%,这主要是由水稻单位面积穗数、每穗粒数、结实率和千粒重的显著降低所致。光头稗和无芒稗处理还显著降低了机械穴直播水稻灌浆期的根系氧化力、剑叶净光合速率、籽粒中玉米素+玉米素核苷含量、灌浆早期的脱落酸含量,籽粒中蔗糖合酶、ADP葡萄糖焦磷酸化酶、淀粉合酶和淀粉分支酶的活性以及成熟期的地上部干物质积累量,上述生理指标的降低可能是机械穴直播水稻在与稗草共生过程中产量降低的重要原因。

25%丙草胺CS对水稻直播田杂草的防除效果和作物安全性评价

为评价新制备的25%丙草胺微囊悬浮剂(CS)的应用效果,参照农药田间药效试验准则开展了水稻直播田杂草的防除及安全性试验。试验结果表明25%丙草胺CS以施用剂量450~877.5 g a.i./hm^(2)进行喷雾处理,其对水稻直播田稗草、鸭舌草等杂草表现出较好的防治效果和持效性,且其对水稻的成苗数、株高、根长、株鲜重、根鲜重等生长指标无明显影响,这一结果为除草剂的合理使用提供了良好的借鉴作用,建议推荐剂量为450~877.5 g a.i./hm^(2),于播种后2 d水稻立针期和杂草未出苗时喷施。

水稻—油菜轮作模式下稻套油栽培技术

油菜是重要油料作物之一,水稻套播油菜作为稻油轮作生产的一项重要农业技术,对提高粮油产量,实现农业可持续发展具有重要意义。本文分析了稻套油模式的优势以及栽培技术要点,为推广油稻轮作栽培技术提供参考。

宣粳糯7号选育及作麦茬稻种植的高产栽培技术

本文分析了宣粳糯7号的选育过程及其特征特性,并从机插秧和直播两种栽培模式总结其作为麦茬稻的高产栽培技术。选育方面宣粳糯7号是以宣粳糯1号为母本,粳糯86120-5为父本经过系统选育而成的早熟晚粳糯稻品种,具有耐迟播、抗逆性强和适应性广等品种特性,适宜机插秧和直播作麦茬稻种植。作麦茬稻高产栽培技术原则是在有足够的有效穗数基础上,促壮秆、成大穗和增粒重,配合病虫草害防治。具体措施包括适时适量播种、科学肥水管理、综合防治病虫草害和适时收获等,机插秧还要求匀栽密植、插足基本苗。目的在于为该品种的推广种植提供参考。

38%敌稗·唑酰草胺·异草松乳油对直播水稻田一年生杂草的防治效果

为明确38%敌稗·唑酰草胺·异草松乳油对直播水稻田一年生杂草的防除效果及其对水稻生长的安全性。参照《农药田间药效试验准则(一)》于2023年在水稻3~4叶期、杂草2~4叶期采用茎叶喷雾法开展大田试验。38%敌稗·唑酰草胺·异草松乳油以有效成分用药量684.0~855.0 g a.i./hm^(2)进行茎叶喷雾,可有效防除稗草、千金子、丁香蓼、异型莎草等一年生杂草,药后40 d株防效89.7%~94.5%,鲜重防效92.4%~96.9%。38%敌稗·唑酰草胺·异草松乳油能够有效防除直播水稻田一年生杂草,且对水稻安全,杀草速度较快。

18%噁唑酰草胺·噁嗪草酮乳油防除直播水稻田一年生禾本科杂草效果研究

为明确18%噁唑酰草胺·噁嗪草酮乳油对直播水稻田一年生禾本科杂草的防除效果及其对水稻的安全性。参照GB/T 17980.40—2000《农药田间药效试验准则(一)》于2023年在水稻2.5~4叶期,禾本科杂草2~4叶期采用茎叶喷雾法开展大田试验。试验结果显示18%噁唑酰草胺·噁嗪草酮乳油有效成分用药量108.0~135.0 g a.i./hm^(2),可有效防除稗草、马唐、千金子等一年生禾本科杂草,药后30 d株和鲜重防效分别为89.07%~92.51%和92.00%~94.13%。18%噁唑酰草胺·噁嗪草酮乳油能够有效防除直播水稻田一年生禾本科杂草,且对水稻生长安全,杀草速度较快。

黄淮海平原高盐低产田水稻覆膜旱直播滴灌栽培技术的建立及应用效果

水稻旱直播覆膜滴灌栽培技术是一项高效节水农业技术,实现了给水和施肥一体化操作,在农业生产用水紧张的地区有很好的利用前景。为了探索该技术在黄淮海平原高盐低产田中应用效果,选取100份抗旱耐盐粳稻品种为材料进行试验研究。结果表明,100个粳稻品种中,平均幼苗成活率大于80.0%品种有15个;分蘖数大于11.0的有12个;株高大于80.0 cm的有10个;最终筛选到3个理论产量大于400.0 kg/667 m^(2)的品种。同时通过测量水稻各个生长期膜下土壤的含盐量,发现采用该技术可以将土壤含盐量从0.7%降低至0.2%,大幅减小了盐胁迫对水稻生长的影响。该技术不仅可以在黄淮海平原水稻旱直播中应用,也为当地的高盐低产田改造提供了一个新的方案。

稻田旋耕直播油菜产量及植株性状的相关分析

为了解稻田旋耕直播条件下油菜产量以及植株性状的变化,选用130个油菜新组合,分析直播油菜产量、植株性状、分枝性状与单株产量间的关系。结果表明,直播油菜不同材料组合间产量存在极显著差异,产量变幅为241.85~137.26 kg/667 m^(2),平均为193.70 kg/667 m^(2);回归分析表明,一次分枝数、单株分枝角果比、一次分枝结角长度与单株产量呈显著正相关,主序结角长度、主序有效角与单株产量相关不显著;直播油菜分枝大于主序对产量的贡献,随分枝结角长度的增加,单株产量逐渐增高。通过选育一次分枝数多、分枝角果数多、分枝结角长度长的材料来提高育成材料的单株角果数及单株产量,从而实现提高直播油菜产量。

机械水直播稻田随播随用芽前除草剂筛选及其安全性评价

采用田间小区试验法开展机械水直播稻田随播随用芽前除草剂防除杂草效果及其对水稻的安全性评价研究。结果表明:4%双唑草腈SC 1 500 m L∕hm^(2)对千金子、异型莎草、耳基水苋菜和陌生菜防除效果优异,10%嘧草醚WP 450 g∕hm^(2)对稗草防除效果优异,两者混用能够有效扩大杀草谱,并可安全应用于机械水直播稻田。4%双唑草腈SC 1 500 m L∕hm^(2)+300 g∕L丙草胺EC 1 125 m L∕hm^(2)、4%双唑草腈SC 1 500 m L∕hm^(2)+10%嘧草醚WP 375 g∕hm^(2)于水稻机械直播后随播随用,对稗草、千金子、异型莎草、耳基水苋菜和陌生菜等稻田主要杂草的防效均可达96.7%—100%,且对水稻出苗率、株高和地上部鲜重均无不良影响,防除效果和安全性与常用对照药剂30%苄嘧·丙草胺OD 1 500 m L∕hm^(2)+专用安全剂375 m L∕hm^(2)无显著差异,生产上可进行交替使用。

3种除草剂组合对水直播稻田杂草的防除效果研究

除草剂单一使用易使杂草产生抗性。本研究通过田间试验比较了3种除草剂组合[(1)土壤喷雾30%苄嘧磺隆·丙草胺可分散油悬浮剂后,茎叶喷雾40%氰氟草酯·噁唑酰草胺可分散油悬浮剂+10%氟嘧啶草醚可分散油悬浮剂(Z-1);(2)茎叶喷雾15%噁唑酰草胺·二氯喹啉酸可分散油悬浮剂+20%氰氟草酯可分散油悬浮剂+43%2-甲-4-氯·氯氟吡氧乙酸可分散油悬浮剂(Z-2);(3)茎叶喷雾15%噁唑酰草胺乳油+20%氰氟草酯可分散油悬浮剂+43%2-甲-4-氯·氯氟吡氧乙酸可分散油悬浮剂(Z-3)]对水直播稻田杂草的防除效果,拟筛选高效除草剂组合,以期延缓杂草抗性发展。结果表明,第2次施药后30 d,3种除草剂组合对禾本科杂草千金子、莎草科杂草、丁香蓼及其他阔叶杂草等的鲜重防效均为100.00%,对稗属杂草的鲜重防效达93%以上,对总草的鲜重防效为93.34%~99.97%。综合分析,上述3种除草剂组合均能有效控制水直播稻田杂草,其中处理Z-1效果最好。

小麦对直播稻田千金子的化感作用及化感物质分离鉴定

研究了小麦茎根水提取液对直播稻田千金子的化感作用,并分离鉴定了化感物质。结果表明:扬麦158和扬麦10号不同生育期的水提取液对千金子种子萌发均有抑制作用,但对幼苗生长无抑制作用;对水稻种子萌发及幼苗生长均无抑制作用;利用室内生测及GCMS分析鉴定抑制千金子种子萌发的化感物质为有机酸,对千金子种子萌发的抑制率达94.90%,有机酸的主要成分为棕榈酸、油酸、亚油酸、硬脂酸及肉豆蔻酸。

酸雨对水稻、小麦和油菜种子萌发的影响

采用pH2 0、2 5、3 0、3 5、4 0与 5 0模拟酸雨处理水稻、小麦和油菜种子的实验结果表明 ,3者在pH 2 0时不发芽 ,在pH 2 5时只有水稻和小麦异状发芽 ,pH≥ 3 0时 ,水稻、小麦和油菜种子的发芽率、发芽势、发芽指数、活力指数都与pH值显著正相关 ,水稻和小麦的异状发芽率则随pH值上升而降低 .部分生理指标的实验结果表明 ,水稻、小麦和油菜的吸水值、呼吸速率和贮藏物质运转效率也与 pH值显著正相关 ,水稻与小麦贮藏物质消耗率与pH值显著正相关 ,而油菜与 pH值显著负相关 ;水稻、小麦和油菜的芽、根长抑制指数都与 pH值显著负相关 .酸雨胁迫下 ,种子各项指标变幅为水稻 <小麦 <油菜 ,这表明抗酸雨胁迫能力为水稻 >小麦 >油菜 .

不同种植制度对稻田旱作季节CH_4和N_2O排放的影响

通过大田试验研究了稻田旱作季节几种典型种植制度对CH4和N2O排放的影响,包括休闲(fallow)、油菜对照(OR-ck)、小麦对照(W-ck)、油菜施N(OR-N)和小麦施N(W-N)5个处理。试验结果表明,稻田旱作季节N2O排放明显,CH4排放量较低,甚至表现为弱的CH4汇。稻田旱作季节N2O排放除受到N肥和种植制度影响外,还受土壤含水量影响,施N处理显著促进了N2O排放,降雨后N2O排放明显。小麦和油菜施N处理N2O平均排放通量分别为18.51和13.47μg.m-2.h-1,季节累积排放量分别为87.31和59.48 mg.m-2,均显著高于对照和休闲处理。不同作物种类间N2O平均排放通量无显著差异,N2O季节累积排放量则表现为小麦显著高于油菜。各处理综合温室效应(100 a)依次为:OR-N>W-N>W-ck>fallow>OR-ck。各施N处理综合温室效应以N2O为主,但各无N处理则以CH4为主,也不容忽视。

双草醚防除直播稻田杂草试验

1996～ 2 0 0 0年试验结果表明 ,农美利对稗草、稻李氏禾、雨久花、泽泻、野慈姑、异型莎草、葡茎剪股颖、谷精草、萤蔺、针蔺等大多数水田杂草有较好的防效。从安全性和除草效果考虑 ,其适宜的施用剂量为 2 2 5～ 3 0 ga i /hm2 ,适宜的施药期为水稻 2～ 4叶期、稗草 2 0～ 4

除草剂对旱直播稻田杂草防效和水稻幼苗的影响

本试验研究了播前灭生性除草剂草甘膦、通杀1号,播后苗前土壤封闭除草剂稻草闭、扫茀特对旱直播稻田杂草的防除效果及其对水稻的安全性。结果表明:草甘膦、通杀1号、稻草闭,扫茀特对总草的株防效分别达到91.42%、89.77%、85.63%、77.87%,其中稻草闭处理的株防效显著高于扫茀特;成秧率分别达到72.3%、68.7%、65.0%,64.8%,草甘膦、通杀1号处理的成秧率均显著高于对照。草甘膦、通杀1号处理显著提高了秧苗茎基宽、地上部鲜重、地上部干重和单位苗高干重等指标,稻草闭与扫茀特处理的秧苗在这些指标上与对照无显著差异。草甘膦处理降低了秧苗POD活性、MDA含量,通杀1号处理则相反,两处理均升高了秧苗CAT活性;稻草闭与扫茀特处理均降低了秧苗POD、CAT活性,升高了MDA含量。这4种除草剂的安全性均较好。