White bean (Phaseolus vulgaris) tolerance to preplant-incorporated herbicides

There is a limited number of registered herbicides in white beans. Field trials were conducted at two Ontario, Canada, locations (Exeter and Ridgetown) in 2001 and 2002 to evaluate tolerance of two white bean cultivars, AC Compass and OAC Thunder, to preplant-incorporated applications of S -metolachlor plus imazethapyr (1600 + 75 and 3200 + 150 g ai ha⁻¹, respectively), flumetsulam plus S -metolachlor ( premixed at 1443 and 2886 g ai ha⁻¹) and cloransulam-methyl (35 and 70 g ai ha⁻¹). There were no differences between the two cultivars in their responses to the herbicide treatments. S -metolachlor plus imazethapyr caused as much as 5% visual crop injury and decreased plant height up to 20%, shoot dry weight up to 39% and yield as much as 21%. Flumetsulam plus S -metolachlor caused as much as 7% visual crop injury and reduced plant height by up to 25%, shoot dry weight by up to 46% and yield as much as 24%. Cloransulam-methyl caused as much as 10% visual crop injury and decreased plant height up to 35%, shoot dry weight up to 55% and yield as much as 44%. There were no differences in seed moisture content among any of the herbicide treatments. This research suggests that the margin of safety of white bean is inadequate to support the preplant-incorporated registration of S -metolachlor plus imazethapyr, flumetsulam plus S -metolachlor and cloransulam-methyl in Ontario.     

Tolerance of adzuki bean to preplant-incorporated, pre-emergence, and post-emergence herbicides in Ontario, Canada

Weed management options for adzuki-bean growers in Ontario, Canada are limited due to few herbicide registrations. Four field trials were conducted at three locations in south-western Ontario in 2007 and 2008 to determine the tolerance of adzuki bean to several preplant-incorporated (PPI), pre-emergence (PRE), and post-emergence (POST) herbicides. All the herbicides were applied at the doses registered for use in soybean. The application of pendimethalin, cloransulam-methyl, and halosulfuron-methyl (PPI), flumetsulam, cloransulam-methyl, and halosulfuron-methyl (PRE), and acifluorfen and fomesafen (POST) caused ≤15% crop injury; however, the injury was transient and did not reduce the adzuki bean yield. The POST application of cloransulam-methyl and imazethapyr caused ≤23% crop injury and reduced the biomass by ≤50%, but did not reduce the plant height or crop yield. Metribuzin, flumetsulam, atrazine, and pyroxasulfone (PPI), metribuzin, linuron, pyroxasulfone, and atrazine (PRE), and bentazon, imazethapyr plus bentazon, halosulfuron-methyl, and thifensulfuron-methyl (POST) caused ≤61% crop injury. These treatments reduced the biomass, plant height, and crop yield. Based on these results, pendimethalin, cloransulam-methyl, and halosulfuron-methyl applied PPI, flumetsulam, cloransulam-methyl, and halosulfuron-methyl applied PRE, and acifluorfen and fomesafen applied POST might be potential weed management options for weed management in adzuki bean. Cloransulam-methyl and imazethapyr applied POST will need further evaluation due to phytotoxicity concerns. Metribuzin, flumetsulam, atrazine, and pyroxasulfone applied PPI, metribuzin, linuron, atrazine, and pyroxasulfone applied PRE, and bentazon, imazethapyr plus bentazon, halosulfuron-methyl, and thifensulfuron-methyl applied POST did not have an adequate margin of safety.     

Responses of otebo bean (Phaseolus vulgaris L.) to postemergence herbicides

Ontario otebo bean growers have few herbicide options available for weed management. Six field trials were conducted in Ontario, Canada, over a 2 year period (2003 and 2004) to evaluate the tolerance of otebo bean to the postemergence (POST) application of bentazon at 1080 and 2160 g ai ha⁻¹, fomesafen at 240 and 480 g ai ha⁻¹, sethoxydim at 500 and 1000 g ai ha⁻¹, quizalofop-p-ethyl at 72 and 144 g ai ha⁻¹, imazamox plus fomesafen at 25 + 200 and 50 + 400 g ai ha⁻¹, and imazamox plus bentazon at 25 + 600 and 50 + 1200 g ai ha⁻¹. All treatments, including the untreated control, were maintained weed-free during the growing season. The POST application of bentazon, imazamox plus fomesafen, and imazamox plus bentazon caused as much as 9% visual injury and reduced the plant height ≤ 12%, reduced the shoot dry weight ≤ 32%, and delayed maturity but had no adverse effect on the yield of otebo bean. Fomesafen, sethoxydim, and quizalofop-p-ethyl applied POST caused as much as 8% visual injury but this was transient and had no adverse effect on the plant height, shoot dry weight, seed moisture content, and yield of otebo bean, except for quizalofop-p-ethyl, which reduced the shoot dry weight as much as 18%. Based on these results, bentazon, fomesafen, sethoxydim, quizalofop-p-ethyl, imazamox plus fomesafen, and imazamox plus bentazon applied POST have an adequate margin of crop safety for weed management in otebo bean production in Ontario. However, care must be taken to avoid spray overlaps to prevent injury from bentazon, imazamox plus fomesafen, and imazamox plus bentazon.     

Characterization and diagnostic tests of resistance to acetohydroxyacid synthase inhibitors due to an Asp376Glu substitution in Amaranthus powellii

A population of Amaranthus powellii that had survived imazethapyr did not have any of the documented AHAS mutations causing resistance in this species in Ontario. The goal of this research was to confirm resistance in this population, determine its molecular basis and develop diagnostic tests. Whole plant dose-response experiments showed the resistant population had greater than 25-fold resistance to the selective agent imazethapyr at the whole plant level. Whole plant resistance to other herbicides ranged between 9-fold to flumetsulam and 85-fold to flucarbazone. This was confirmed at the enzyme level with resistance ranging between 25-fold to imazethapyr and 485-fold to thifensulfuron. AHAS from the resistant population had 16% higher specific activity than that of the susceptible population and it was also less sensitive to feedback inhibition by valine, leucine and isoleucine. Genomic DNA was extracted to PCR amplify and sequence the AHAS gene and to determine the applicability of diagnostic tests. Sequencing of the AHAS gene revealed a single point mutation of thymine₁₁₂₅ to guanine coding for an Asp₃₇₆Glu substitution. Two different diagnostic tests, restriction fragment length polymorphism and PCR amplification of specific allele, were able to correctly identify the resistant population from the susceptible control and from other resistant populations. Although this mutation appears to confer higher resistance to pyrithiobac and flucarbazone, two herbicides not registered in Eastern Canada, it endows plants with enough protection to allow survival to imazethapyr, the main selective agent in Ontario.     

Response of black, cranberry, kidney, and white bean to linuron

Dry bean producers in Ontario, Canada, have few herbicide options available for annual broad-leaved weed management and there is little information on the tolerance of dry bean to linuron. The tolerance of black, cranberry, kidney, and white bean to the pre-emergence (PRE) application of linuron at the rates of 0, 500, 1000, 1500, 2000, and 2500 g ai ha⁻¹ was evaluated in field studies conducted in 2005 and 2006 at Exeter and in 2006 at Ridgetown, Ontario. The four market classes differed in their response to linuron. Cranberry and kidney bean were more tolerant to the PRE application of linuron than black and white bean. Linuron applied PRE caused as much as 12% injury in cranberry and kidney bean, 47% injury in black bean, and 56% injury in white bean. Linuron applied PRE at 500–2500 g ai ha⁻¹ had no effect on the height of cranberry and kidney bean but decreased the height by 7, 8, and 15% in black bean and by 10, 13, and 23% in white bean at 1500, 2000, and 2500 g ai ha⁻¹, respectively. Linuron applied PRE at the rates evaluated did not cause any adverse affect on the yield of cranberry, kidney, and white bean but black bean yield was reduced by 16% at 2500 g ai ha⁻¹. Based on these results, there is not an adequate margin of crop safety for the PRE application of linuron in black and white bean at rates >1000 g ai ha⁻¹. However, there is a potential for the use of linuron PRE for weed management in cranberry and kidney bean at the rates evaluated.     

Tolerance of black, cranberry, kidney, and white bean to cloransulam-methyl

The level of tolerance of various market classes of dry bean to cloransulam-methyl is not known. Three field studies were conducted in Ontario, Canada during 2007 and 2008 to determine the level of tolerance of black, cranberry, kidney, and white bean to the pre-emergence (PRE) and postemergence (POST) application of cloransulam-methyl at 17.5, 35, and 70 g ai ha⁻¹. Cloransulam-methyl applied at 17.5, 35, and 70 g ha⁻¹ caused between 13 and 23% injury in black, cranberry, kidney, and white bean, respectively. Cloransulam-methyl applied at 17.5, 35, and 70 g ha⁻¹ reduced the shoot dry weight by between 16 and 28% compared to the untreated control. Cloransulam-methyl applied PRE reduced the height of black bean by 27% and the height of cranberry bean by 25% at 70 g ha⁻¹ and reduced the height of white bean by 19% at 35 g ha⁻¹ and by 37% at 70 g ha⁻¹. Cloransulam-methyl applied PRE reduced the yield of black bean by 29% at 35 g ha⁻¹ and by 43% at 70 g ha⁻¹, reduced the yield of cranberry bean by 43% at 70 g ha⁻¹, and reduced the yield of white bean by 36% at 35 g ha⁻¹ and by 54% at 70 g ha⁻¹. Based on these results, there is not an adequate margin of crop safety for the PRE and POST application of cloransulam-methyl in black, cranberry, kidney, and white bean at the rates evaluated.     

28种除草剂对大豆的安全性及药害研究初报

28种除草剂对大豆安全性田间试验结果表明 ,适用于大豆田使用的几种除草剂中 ,广灭灵、施田补和氟乐灵在推荐剂量下应用对大豆安全 ;精禾草克、拿捕净和威霸使用推荐量或加倍量对大豆均安全 ;赛克、速收、乙草胺、都尔和普乐宝在正常剂量和正常气候条件下对大豆安全 ,药后低温多雨或土壤湿度大时会产生一定程度的药害 ;豆磺隆、宝收、阔草清、2 ,4 -滴丁酯作土壤处理时对大豆安全 ,而作茎叶处理时会产生药害 ;茎叶处理剂虎威、杂草焚、克阔乐、利收、普施特、金豆等 ,正常剂量下也有产生药害 ,但可以恢复正常生长 ;而百草敌、2甲 4氯、玉农乐、宝成、百农思、伴地农和阿特拉津等非适用于大豆田的除草剂 ,使用正常剂量就能使大豆产生相当程度的药害甚至死亡     

Biological responses to glyphosate drift from aerial application in non‐glyphosate‐resistant corn

BACKGROUND: Glyphosate drift from aerial application onto susceptible crops is inevitable, yet the biological responses to glyphosate drift in crops are not well characterized. The objectives of this research were to determine the effects of glyphosate drift from a single aerial application (18.3 m swath, 866 g AE ha^?1) on corn injury, chlorophyll content, shikimate level, plant height and shoot dry weight in non‐glyphosate‐resistant (non‐GR) corn. RESULTS: One week after application (WAA), corn was killed at 3 m from the edge of the spray swath, with injury decreasing to 18% at 35.4 m downwind. Chlorophyll content decreased from 78% at 6 m to 22% at 15.8 m, and it was unaffected beyond 25.6 m at 1 WAA. Shikimate accumulation in corn decreased from 349% at 0 m to 93% at 15.8 m, and shikimate levels were unaffected beyond 25.6 m downwind. Plant height and shoot dry weight decreased gradually with increasing distance. At a distance of 35.4 m, corn height was reduced by 14% and shoot dry weight by 10% at 3 WAA. CONCLUSIONS: Corn injury and other biological responses point to the same conclusion, that is, injury from glyphosate aerial drift is highest at the edge of the spray swath and decreases gradually with distance. The LD₅₀ (the lethal distance that drift must travel to cause a 50% reduction in biological response) ranged from 12 to 26 m among the biological parameters when wind speed was 11.2 km h^?1 and using a complement of CP‐09 spray nozzles on spray aircraft. Published 2010 by John Wiley & Sons, Ltd.     

绿豆田土壤处理除草剂筛选

采用田间试验和室内生测相结合的方法研究了5种土壤处理除草剂对绿豆的安全性和对杂草的防效,筛选适于内蒙古中部绿豆田使用的化学除草剂。田间试验结果表明,在常规用量处理下,33%二甲戊灵乳油990g/hm2、50%扑草净可湿性粉剂750g/hm2和96%精异丙甲草胺乳油1 152g/hm2处理对绿豆田一年生杂草的防效分别为92.4%、91.9%和90.3%,80%唑嘧磺草胺水分散粒剂48g/hm2处理对一年生阔叶杂草的防效在94%以上。田间安全性调查及测产结果显示,上述4种除草剂常量处理和倍量处理的绿豆出苗数、根系鲜重、茎叶鲜重、株高等指标及产量性状指标均与空白对照差异不显著。室内结果表明,这4种除草剂的施药量增加到常用量的3倍后,对绿豆生长仍比较安全。从除草剂药效和作物安全性考虑,33%二甲戊灵乳油、50%扑草净可湿性粉剂、96%精异丙甲草胺乳油和80%唑嘧磺草胺水分散粒剂可推荐用于内蒙古中部绿豆田。     

基于连续14年国家绿豆品种区域试验的中国绿豆品种产量和性状变化

利用GGE双标图、变异系数法、相关性分析、多元回归和聚类分析等方法,分析了2003—2016年共14 a国家绿豆品种区域试验中来自内蒙古自治区、黑龙江省、吉林省、辽宁省、山西省等12个绿豆主产省（市、自治区）的29个育种单位提供的130个参试品种的生育天数、株高、主茎节数、主茎分枝数、荚长、单株荚数、荚粒数、千粒重以及产量在春播组和夏播组的变异,并比较了性状间的相关性以及不同育种单位选育的绿豆品种的性状差异。结果表明：2003—2016年春播组和夏播组绿豆产量分别增加14.0%和25.4%,年均增幅分别为1.0%和1.8%;主茎分支数分别减少12.0%和15.9%;其他性状变化不明显。春播组绿豆主要农艺性状的变异系数为5.14%~17.01%,均值为11.33%;遗传多样性指数为1.91~2.08,平均为1.99。夏播组绿豆主要农艺性状的变异系数为5.96%~19.99%,均值为12.52%;遗传多样性指数为1.98~2.17,平均为2.07。相关性和偏相关性分析表明,春播组中产量与荚长、单株荚数和荚粒数显著正相关,与其他性状的相关性不明显;夏播组中产量与单株荚数和荚粒数显著正相关,与株高、主茎分支数和荚长显著负相关。多元回归分析表明,春播组绿豆生育天数、株高、主茎分支数、荚长和单株荚数共同决定产量60.9%的变异;夏播组绿豆株高、主茎分枝数、单株荚数、荚粒数和千粒重共同决定产量87.7%的变异。依托品种选育区域的聚类分析表明,65个春播组品种被分为4类,在北京市、河北省、山西省、河南省、山东省、吉林省和陕西省综合表现较好;65个夏播组品种被分为6类,在河南省、河北省和山东省综合表现较好。2003—2016年,国家每轮区试的绿豆品种产量稳步提升,表明我国绿豆育种水平有了一定提升;但品种遗传基础狭窄,育种方法多样化程度较低,缺少突破性品种。     

Ameliorative Effects of Brassinosteroids on Growth and Productivity of Snap Beans Grown Under High Temperature

The effect of brassinosteroids (BRs) was tested, in order to assess the possibility of alleviation of the adverse effects of high temperature stress on snap bean plants during delayed summer cultivation. Therefore, two field experiments were carried out in successive seasons, 2010 and 2011, with two bean cultivars ‘Paulesta’ and ‘Oxzira’, spraying with BRs of the following concentrations 0 (control), 25, 50 and 100 ppm. Plant growth, yield and pods quality of beans were studied. Spraying bean plants with BRs at a concentration of 25 and 50 ppm increased vegetative growth, total yield and quality of pods with no significant difference between both treatments. Using BRs at 25 ppm increased the total free amino acids (FAA) in leaves and total phenolic acids in the pod in comparison to control-treatment. ‘Oxzira’ cultivar resulted in the highest number of leaves, number of branches, dry weight of whole plant, total yield, total FAA in leaves and total phenolic acids in pod. Whereas, ‘Paulesta’ cultivar had the highest of plant length and total FAA in pods.     

乙烯利-甲哌 FDA4 复配剂对夏玉米生育及产量的影响

在玉米大喇叭口期叶面喷施乙烯利-甲哌 FDA4 复配剂,能起到改善株型结构、促进同化物分配转运和提高产量的综合效果。具体表现为:1)增加气生根数和根系干重;2)缩短节间长度、增加茎粗,降低株高和穗位高,提高茎粗系数;3)促进灌浆初期同化物向根系分配、灌浆中期在地上部营养器官内积累、灌浆后期向产量器官转运,并有利于玉米提早成熟;4)提高双穗率、增加穗数,减少秃尖、增加行粒数,显著提高玉米单产。上述结果表明,乙烯利-甲哌 FDA4 复配剂能起到防止倒伏、提早成熟的作用,在夏玉米生产中具有较好的应用推广价值。     

非转基因抗除草剂玉米对三种乙酰乳酸合成酶抑制剂类除草剂的田间抗性表现

为评估中国农业大学培育的非转基因抗除草剂玉米品系958R和335R在大田条件下对乙酰乳酸合成酶（acetolactate synthase,ALS）抑制剂类除草剂的抗性表现,利用甲咪唑烟酸、砜嘧磺隆、唑嘧磺草胺3种除草剂对郑单958、958R、先玉335、335R共4种玉米杂交种进行了播后苗前土壤处理,每种除草剂设3个处理剂量（1、3、9倍推荐剂量）,并于施药2周和4周后进行株高测定,于收获晾干后测产。结果表明,在甲咪唑烟酸216、648 g（a.i.）/hm²处理下,郑单958和先玉335均已绝产,而958R和335R产量均未受影响;在砜嘧磺隆或唑嘧磺草胺高剂量处理下,常规玉米品种郑单958和先玉335株高的最高降幅分别为25.7%和35.2%,田间药害反应显著,而958R和335R则抗性反应显著。研究表明,非转基因抗除草剂玉米杂交种具有良好的田间抗性,不仅能有效解决玉米田砜嘧磺隆和唑嘧磺草胺等ALS除草剂的药害问题,还能够通过引入甲咪唑烟酸等新的ALS除草剂更好地防除玉米田的杂草。     

Tillage implement effects on herbicide efficacy and the yield of cotton grown under a sprinkler or drip irrigation system

Field experiments were conducted during 2003 and 2004 at four locations in northern Greece to evaluate the effects of tillage implements and herbicide treatments on the weed control and yield of cotton grown under a mobile sprinkler or drip irrigation system. The tillage implements consisted of three seedbed preparation tillage implements: a field cultivator with a double rolling basket, a disk harrow or a rotary harrow. The herbicide treatments consisted of a broadcast preplant-incorporated (PPI) application of trifluralin or S-metolachlor followed by pre-emergence (PRE)-applied prometryn, a PRE 38 cm band application of S-metolachlor plus fluometuron or a broadcast PPI application of S-metolachlor followed by early postemergence-applied trifloxysulfuron-sodium. In most cases, the PPI applications followed by the PRE application of prometryn resulted in the greatest control of black nightshade ( Solanum nigrum L.), redroot pigweed ( Amaranthus retroflexus L.), and common lambsquarters ( Chenopodium album L.). The control of black nightshade and common lambsquarters was slightly reduced when the herbicides were incorporated by rotary harrow. The cotton yield was not affected in most cases by the tillage implements, while the drip irrigation system provided a greater or similar cotton yield as compared with the sprinklers. The PPI application of trifluralin followed by the PRE-applied prometryn in the cotton grown under drip irrigation provided the greatest lint yield in most cases. Therefore, a drip irrigation system and disk harrow or field cultivator implement could be used as the first choice of cotton growers in integrated crop management production systems.     

河南黄淮麦茬稻区适宜旱稻品种 及鉴定指标的筛选

为筛选适合河南黄淮麦茬稻区种植的优良旱稻品种,建立适宜的旱稻鉴定评价体系,利用河南地区主要推广的23个水、旱稻为材料,于旱棚内旱直播种植,在孕穗期和成熟期对植株形态、生理生化性状和单株产量进行测定和分析。结果表明,水分胁迫条件下,高产品种的平均单株产量、分蘖数、株高、地上部鲜重和根基粗分别是低产品种的2.46、1.78、1.17、1.57和1.18倍,分蘖数、株高、地上部鲜重和根基粗与旱田单株产量呈显著正相关。旱田产量和分蘖数可以作为河南黄淮麦茬旱稻的评价指标,株高、地上部鲜重和根基粗可以作为辅助指标。初步筛选洛稻998、徐旱702、原旱稻3号和郑旱2号为适宜推广的高产抗旱品种。     

土壤湿度对蚕豆根病及其生长的影响

 土壤湿度是影响蚕豆(Vicia faba L.)生长和根腐病发生的主要环境因素之一。本文以来源于蚕豆产区的田间土壤,分别以30%、50%和70%的土壤饱和持水量(WHC)处理进行盆栽试验,在室外自然条件下生长,测定了出苗率、出苗速度、株高、生长速度、叶面积、总叶绿素含量、净光合速率、结荚数、根瘤数、生物量干重、根腐病严重度及死亡率。结果表明50% WHC的土壤含水量为蚕豆生长的最佳土壤湿度,有利于蚕豆健康生长,减少根腐病的发生与危害。在30%、50%和70%WHC土壤湿度条件下,播后10周蚕豆生物量干重和植株的死亡率依次分别为1.53、3.16、2.68g和18.5%、4.8%、25.6%。     

Selection for resistance to the herbicide imazethapyr in somaclones of soyabean

Cultivars of soyabean [ Glycine max (L.) Merr.] resistant to the herbicide imazethapyr were identified by suspending the roots of 5-day-old seedlings in nutrient culture containing 2.5 mg a.i. L^–1 imazethapyr and then comparing the inhibitory effect on root length and shoot dry weight. The four most resistant cultivars were subsequently screened as regenerating tissue cultures in a medium containing 2.0 mg a.i. L^–l imazethapyr to select somaclonal cells with increased resistance. Surviving portions of cultures were regenerated to give shoots, the plants isolated, allowed to flower and seed. These progeny were then used for further seed multiplication and seedlings from this latter generation were exposed to imazethapyr in vivo and callus and cell suspension cultures derived from these seedlings were exposed to imazethapyr in vitro . A reduction in the inhibitory effect of the imazethapyr was noted in the somaclone seedlings and tissue cultures. However, measurement of acetolactate synthase (ALS) activity showed no differences among the parent cultivars and in the selected somaclones in this trait.     

The allelopathic effect of three Amaranthus spp. (pigweeds) on wheat (Triticum durum)

The allelopathic effect of Amaranthus retroflexus L., Amaranthus blitoides S. Wats, and Amaranthus gracilis Desf. on wheat Triticum durum L. was investigated under laboratory, glasshouse and field conditions. Laboratory experiments showed that fresh shoot or root extract of the three weed species reduced germination, coleoptile length, root length and root dry weight of wheat seedlings. The inhibitory effects were rate dependent, with low concentrations of shoot extract promoting shoot growth of wheat. Fresh plant extracts were more phytotoxic than dried plant extracts and shoot extracts had higher detrimental effects than root extracts. In pot experiments, dried shoot extract of A. gracilis increased shoot and root dry weights of wheat seedlings. For A retroflexus and A. blitoides the extracts of these and dried shoots (8 g kg^?1), which had been added to soil mixtures significantly reduced ger-mination and growth of wheat seedlings. Addition of up to 16 g kg^?1 of A. gracilis residues promoted shoot growth of wheat and had no significant harmful effect on root growth. Roots appeared more sensitive to allelopathic effect than shoots. Under field conditions, incorporation of A. retroflexus or A. blitoides residues in the soil reduced height, grain and straw yield of wheat, whereas A. gracilis residues stimulated plant height and increased yield.     

品种、培养基质和接种量对马铃薯脱毒基础苗生长的影响

以马铃薯早熟品种大西洋、中熟品种克新1号、晚熟品种青薯168脱毒基础苗为试验材料,研究品种、培养基质和接种量对马铃薯脱毒基础苗苗鲜重、根鲜重、苗干重、根干重、叶片数、株高、茎粗、根长和根条数等性状指标的影响,培养14 d时,测定各性状指标。结果表明:三个品种的主要农艺性状均在液体培养基上表现为最佳,其平均单株鲜重、干重、株高、茎粗、节长和根条数分别为:159.4 mg、9.1 mg、7.3 cm、1.16 mm、1.4 cm、5.6条。在液体培养基上,降低了马铃薯工厂化生产成本,同时还可缩短马铃薯脱毒基础苗培养时间7~9 d。接种量对马铃薯单株根鲜重、苗干重、叶片数、株高、茎粗、根长有显著性影响(P<0.05);不同成熟期品种苗鲜重、根鲜重、根干重、叶片数、株高、茎粗、根长和根条数受品种影响显著(P<0.05);不同成熟期品种、不同接种密度处理对马铃薯单株根鲜重、苗干重、根干重、叶片数、株高、茎粗、根长影响有显著性交互作用(P<0.05);早熟品种大西洋,接种密度为0.67株/cm2时,中熟品种克新1号和晚熟品种青薯168接种密度为0.80株/cm2时,综合农艺性状表现最好。     

限量灌溉和施磷对冬小麦生长及水分利用的影响

在大田条件下研究了不同灌水和施磷组合对冬小麦生长及水分利用的影响。结果表明:灌水和施磷均可提高冬小麦的株高、生物量、产量及其产量构成。在不同水分条件下,冬小麦的株高随灌水量的增加而增加,水分对冬小麦的产量和千粒重的影响达到显著水平,而不同水分条件对穗长、穗重和穗粒数没有显著影响。在不同施磷处理下,随着施磷量的增加,分蘖数、穗数、千粒重、产量及其灌溉水利用效率有显著增加,但施磷对株高没有显著影响。本试验条件下,施磷量120 kg/hm2时,株高、干物质及其产量达到最大,当施磷量超过120 kg/hm2时,相关物质生产指标呈下降的趋势;灌水量为180 mm与施磷肥量为120 kg/hm2是冬小麦干物质积累和产量的最优组合。