Effect of Planting Date on the Growth and Yield of Irrigated Sunflower (Helianthus annuus)

The effect of planting date on the growth and yield of irrigated sunflower was investigated in 1992 and 1993. Two sunflower hybrids, Islero and Upsol-veraflor, were sown at three different dates (3 October, 4 November, 2 December 1992 and 5 October, 6 November, 4 December 1993) in Sultan Qaboos University Agricultural Experiment Station on the Batinah Coast of Oman in a desert climate. Sunflower planted in December emerged later, flowered later and matured later than that planted in October or November. Severity of stalk lodging was closely related to the extent of stem weevil infestation, which was more serious in the early planted sunflower. Sclerotina head rot was also most severe in the October plantings and least severe in the December plantings. Head diameter, number of seeds per head and percentage of large seeds increased with delay in planting date. Seed yield and oil yield were highest in the December planted sunflower but oil concentration was not affected by the planting date. Based on these results, a December planting date was recommended for the Batinah Coast of Oman and other areas with similar climatic conditions.     

播期和密度对芸豆生长、干物质积累及产量的影响

基于黑龙江省芸豆主栽地区春季频繁发生低温干旱,生产上经常晚播的生产实际,为了寻求适应实际生产条件的播期和密度协调栽培技术,在大田试验条件下探讨了5月15日(I)、5月25日(II)、6月04日(III)3个播期和15万株/hm~2(D1)、20万株/hm~2(D2)、25万株/hm~2(D3)、30万株/hm~2(D4)4个种植密度对芸豆植株性状、干物质积累及产量的影响。结果表明:相比于第I播期,第II和III播期条件下,芸豆的株高、茎粗、主茎节数和分枝数均有所下降,但芸豆的生长率有所增加。同时,随播期的推迟,芸豆花后的单株干物质积累和群体干物质积累逐渐下降趋势,单株荚数和单株粒数呈先增后减趋势。II-D2处理的产量最高,其次为I-D2和III-D3处理,分别比不同播期下D1处理多27.18%~45.31%、17.57%~34.34%、14.92%~31.31%。总体来看,在3种播期下,合理的种植密度能够使芸豆生长率、花后群体干物质积累增加,构建优良群体结构,在晚播(III)时适度密植(D3)的增产稳产优势更明显。     

向日葵干物质转运及产量对播种期和栽培密度的响应

以油用向日葵T562为供试材料,采用二因素裂区设计,研究了5个播期（4月25日、5月2日、5月9日、5月16日及5月23日）和4个种植密度（3.75×10⁴、4.50×10⁴、5.25×10⁴、6.00×10⁴株/hm²）条件下向日葵干物质转运及产量变化。结果表明：随着播期的推迟,向日葵各生育期均缩短,播期对向日葵出苗至开花阶段影响较大,对开花至成熟阶段影响较小。成熟期植株干物质积累量在不同密度下的均值依次为4.50×10⁴>3.75×10⁴>6.00×10⁴>5.25×10⁴株/hm²。随种植密度的增加单盘粒重逐渐降低,产量逐渐增加。籽仁率在播期5月16日、密度5.25×10⁴株/hm²处理下达最大,为74.09%;百粒重及产量在播期5月2日、密度6.00×10⁴株/hm²处理下达最大,分别为8.76g、6859.00kg/hm²;单盘粒重在播期5月23日、密度3.75×10⁴株/hm²处理下达到最大,为138.14g。     

外源6-BA和ABA对不同播种期棉花产量和品质及其棉铃对位叶光合产物的影响

大田播种期(4月25日和5月25日)和植物生长调节剂(6-BA和ABA)试验于2006年在江苏南京(长江流域下游棉区)和河南安阳(黄河流域黄淮棉区)进行，以科棉1号和美棉33B品种为材料，研究外源6-BA和ABA对不同播种期棉铃对位叶光合产物形成与运转的影响及其与产量品质的关系。结果表明: (1) 6-BA显著提高棉铃对位叶蔗糖含量和转化率及淀粉含量，而ABA则主要调节棉铃对位叶内源激素平衡。(2)不同播种期条件下(4月25日和5月25日)，外源6-BA均可使棉花单铃重增加、纤维品质提高，外源ABA在晚播(5月25日，南京试点和安阳试点棉铃发育期MDT_min分别为20.9℃和16.5℃)条件下可使棉花产量(安阳试点)和纤维主要品质指标下降幅度减小；外源6-BA和ABA对棉籽主要品质性状的作用均不显著。(3)晚播条件下外源6-BA和ABA均可提高相对棉花主要品质指标，但两者作用机制不同，外源6-BA主要是提高棉铃对位叶光合产物含量和蔗糖转化率，而ABA则主要是诱导棉株抗逆性。     

播期对耐密植大豆品种主要农艺性状及产量的影响

为了研究播期对大豆主要农艺性状及产量的影响,以黑龙江省第三积温带大豆主栽耐密植品种合丰51为试验材料,通过5个播期处理（S1为5月10日,S2为5月20日,S3为5月30日,S4为6月9日, S5为6月19日）,研究不同播期条件下大豆主要农艺性状及产量的变化规律。结果表明,随着播期的延迟,株高、主茎节数及百粒重呈逐渐降低的趋势;单株荚数、单株粒数呈先增加后降低趋势;大豆产量随着播期的延迟呈先增加后降低趋势,在S3处理达到最高值,为4214.3kg/hm2。因此,大豆品种合丰51在黑龙江省东部地区的最佳播种时期为5月30日。     

Effect of Planting Date on Seed Yield, Oil Content and Fatty Acid Composition of Safflower (Carthamus tinctorius) Cultivars Grown in the Mediterranean Region of Turkey

A study was conducted to investigate the effect of different planting dates (25 April, 5 May and 15 May 1998 and 30 April, 15 May and 25 May 1999) on the seed yield, oil content and fatty acid composition of three safflower (Carthamus tinctorius) cultivars (Yenice 5‐38, Dincer 5‐118 and 5‐154) grown in fields of the research facility of Akdeniz University in Antalya, Turkey. While seed yield, oil content, and palmitic acid, stearic acid, and oleic acid contents decreased, linoleic acid content increased from 50.86 to 55.72 % with delay in planting date. The effect of genotype on fatty acids was greater than that of environment.     

Field Pea Seeding Management for Semi-arid Mediterranean Conditions

The effects of seeding rate (30, 60 and 90 seeds m^?2), seeding date (14 January, 28 January and 12 February), seed weight (0.18 and 0.25 g seed^?1), seeding depth (3 and 6 cm), and phosphorus fertilization rate (17.5, 35.0 and 52.5 kg P ha^?1) and placement method (banded or broadcasted) on field pea (Pisum sativum L.) development and seed yields were investigated in irrigated field experiments conducted in northern Jordan in 2000 and 2001. Results and treatment responses were consistent in both years. Seeding rate, seeding date, seed weight and rate and method of phosphorus fertilization had significant effects on most traits measured; planting depth however did not affect any of the traits. Generally a positive correlation was observed between each factor and seed yield and yield components, with the exception of a negative correlation between seeding rate and yield components, and seeding date and yield and yield components. Increase in seeding rate from 30 to 90 seeds m^?2, and increase in P fertilization from 17.5 to 52.5 kg ha^?1 alone increased seed yields by 50 and 41 %, respectively. Each delay of 2 weeks for seeding from mid‐January resulted in reductions of 12 % in seed yields. Overall, the results revealed that a combination of early seeding (14 January), of large seeds at an high seeding rate (90 seeds m^?2), with P fertilizer banding (52.5 kg P ha^?1) maximize field pea yields in irrigated fields in semi‐arid Mediterranean environments. With such management pea seed yields can be as high as 2800 kg ha^?1.     

播期对毛叶苕子生长发育及产量的影响

针对内蒙古黄土高原毛叶苕子苗情不稳、低产晚熟等问题,通过连续2年田间小区试验,探究4月10日（ST₁）、4月20日（ST₂）、4月30日（ST₃）和5月10日（ST₄）4个播期下毛叶苕子生育期持续时间、农艺性状、干物质累积和籽粒产量变化规律。结果表明：播期对毛叶苕子各生育期持续时间及出苗率有显著影响,不同播期下毛叶苕子株高、单株荚数、单荚粒数和单株根瘤数差异显著,且干物质积累量呈慢—快—慢增长趋势,其中均以ST₂播期表现最好;在产量方面,2年均以ST₂处理最高,为942.45~1 056.75kg/hm²,籽粒产量同积温和降水量显著相关,且积温对产量的影响最大。综上所述,4月20日播种毛叶苕子能较大程度适应当地水热条件,增加单株荚数、单荚粒数和单株根瘤数,实现稳产高产。4月20日为内蒙古黄土高原毛叶苕子最佳播期。     

Genetic analysis of yield and related traits in sunflower (Helianthus annuus L.) in dryland and irrigated environments

The definition of a suitable breeding strategy in drought-prone environments is an important task for sunflower breeders. To achieve this task, reliable information on heritability and gene effects on yield and related traits under these conditions is necessary. Thirty six sunflower hybrids were produced by factorial cross of six male-sterile and six restorer lines. Parents and their hybrids were evaluated in eight environments. Six environments consisted of two adjacent trials in the experimental area, the first under irrigation and the second under dryland conditions, during 1987, 1988 and 1992. The other environments were: one early planting trial in dryland conditions, conducted during 1987, and a winter trial planted in January during 1988. Estimates of female variance (σ_f) were significant for seeds per head, seed weight, head sterile center, days to blooming and oil content. Female × male interactions (σ² _fm) were significant for all characters except harvest index and index of susceptibility to drought. Estimates of narrow sense heritabilities, calculated with information from analyses combined across environments, were 0.65 for yield, 0.80 for seeds per head, 0.84 for seed weight, 0.81 for head diameter, 0.60 for sterile head center, 0.72 for oil content, 0.61 for harvest index, 0.72 for biomass, 0.94 for days to bloom, and 0.42 for drought susceptibility index. Heritability estimates for individual environments showed more variation for yield than for other traits. Estimates for heritability of canopy temperature were high (0.68–0.79). Rainfed yield was positively correlated with yield components and negatively correlated with canopy temperature and susceptibility index. It is concluded that an efficient breeding strategy for sunflower under moderate drought-stressed conditions is the simultaneous selection for seed yield in both rainfed and irrigated environments together with selection for canopy temperature and stem diameter. This revised version was published online in July 2006 with corrections to the Cover Date.     

播期和密度对马铃薯原种扩繁生长发育及产量的影响

在马铃薯原种生产中,播种密度和播种期对原种繁育的产量、种薯大小等有着明显的影响。选用当地主栽品种大西洋,于2017-2018年在山丹县冷凉区域,同一地点开展不同播期和密度试验。播种选择4月25日、5月5日、5月15日、5月25日和6月5日,种植密度设置60 000、90 000、120 000、150 000和180 000粒/hm ² 5个水平。结果表明,在当地的栽培模式大垄双行覆膜种植下,4月25日-5月15日播种,播种密度为120 000、150 000粒/hm ²,产量在45 285~46 770kg/hm ²,中种薯率在75.3%~79.6%,合格种薯多,均为最高,且此范围产量差异不显著。考虑到节约原原种投入降低成本,生产中优选120 000粒/hm ²的播种密度,在4月25日-5月15日种植,是大西洋原种繁育的最佳选择方案。     

Effect of Date of Planting, Genotype and Source of Seed on Disease Incidence, Yield, and Agronomic Performance of Soybean

Four soybean genotypes chosen from four seed sources were planted in a factorial arrangement on four dates in a split-plot design at the Alabama A & M Experimental Station on a Decatur silt clay loam soil. The highest vigor index was recorded from seeds harvested from the 4th date of planting. These seeds had the lowest level of Diaporthe phaseolorum var. caulivora infection, indicating that vigor index, as a measurement of seed quality, was negatively correlated with the level of infection by soybean stem canker pathogen. Seed yield was highest at the 2nd date of planting and lowest at the 4th date of planting. Tracy-M and Bedford confirmed previous reports on their resistance and susceptibility, respectively, to soybean stem canker. All the genotypes performed their best at the 2nd date of planting. Source of seeds appeared to have little effect on the performance of the plant in the field.     

Effect of Agronomic Factors on Annual Leguminous Forage Crop in Mediterranean Environments

Dry matter and seed production of five annual leguminous species hairy vetch ( Vicia villosa Roth cv. Orsara) , crimson clover ( Trifolium incarnatum L. ecotype Campano) , squarrosum clover ( T. squarrosum L. ecotype Calabro) , persian clover ( T. resupinatum cv. Accadia) and fenugreek ( Trigonella foenum-graecum L. ecotype Maltese) was estimated in 1989–90 under two density and irrigation rates and with two cutting treatments. The experiments were done at the Forage Crops Institute of Foggia, which has a typical Mediterranean environment. The forage cut severely affected the regrowth of the plants in all species. The year and irrigation factors affect dry matter, seed production and seed yield components more than the plant density rates. The averages over the years, for dry matter and seed yield were 21.0 % and 20.5 % higher in the irrigated than the not irrigated ones. The lower plant density rate, for seed yield trait, gave better result in hairy vetch in irrigated and non-irrigated treatment. Whereas in the other species, the lower rate of planting gave greater yield under non-irrigated and the higher rate under irrigated growing condition. The seed yield components most influenced by irrigation were: thousand seed weight and seeds/pod in hairy vetch and heads/tiller and seeds/head in clovers species. Fenugreek was the earliest forage crop (cut at the beginning of March), followed by crimson and persian clovers (cut at the middle of April) and squarrosum clover and hairy vetch (cut in the middle-late of May). All the cultivars and ecotypes considered not regrowth after cut and could represent an important fresh forage resource for the period March–May for the Mediterranean regions.     

Efficiency of water use of early plantings of sunflower

Rain fed crop production in Mediterranean environments depends to a large extent on strategies that avoid the intense summer drought. Early plantings of sunflower have given consistently higher yields in such environments, but the basis for such yield increases has not been explored. We conducted two field experiments at Cordoba (Spain) to investigate the effects of an early and a late planting date on the components of water-limited crop productivity; namely, water use (T), water use efficiency (TE) and harvest index (HI) of sunflower. The results were generalized by simulating rain fed sunflower yields, under early (1 January) and late (15 March) plantings, for a 25-year period with the aid of a simulation model of the Ceres type (OILCROP-SUN) which has been validated in Cordoba. Experimental seed yields of early plantings in 1989 and 1996 were 2.0 and 3.0 t ha⁻¹, while late plantings yields were 1.3 and 2.4 t ha⁻¹, for the 2 years. Average simulated yields were 2.7 ± 1.1 and 1.9 ± 0.7 t ha⁻¹ for early and late plantings, respectively. For the 2 years, T of early plantings was higher than that of late plantings, but the response of TE and HI to planting date was not the same in the two experiments. In the simulation exercise, T and TE of early plantings were consistently higher than those of late plantings, while there were no differences in the HI for the two planting dates. We conclude that early plantings of sunflower increase rain fed yields by increasing both T and TE, while the impact of planting date on HI very much depends on the crop water stress pattern, which is quite variable from year to year even in the predictable Mediterranean environment.     

The Effect of Different Planting Dates on the Infestation of Soybean by Heterodera glycines Race 5

The effects of different planting dates on infestation of susceptible soybean cvs. Essex and Lee by Heterodera glycines were investigated during three growing seasons. Early planting dates of susceptible soybean cvs. at lower temperatures resulted in smaller nodules, lower nematode populations and field infestations, lower soybean cyst nematode (SCN) disease ratings, taller plants, and higher yields. SCN induced more nodules on soybean roots at 14 May plantings date. The development of SCN race 5 in the field was associated closely with soil temperature. The infestation of susceptible soybean cvs. at early planting dates by H. glycines greatly affected the agronomic performance of these cvs. in the field. Susceptible soybean cvs grown in infested soil with SCN race 5 planted earlier than the recommended planting dates escaped severe infestation of SCN in the field.     

灌溉方式和播期对玉米水分动态与水分利用效率的影响

为明确不同灌溉方式、不同播期下产量与水分利用效率和耗水量的关系,通过设置滴灌、喷灌、漫灌3种灌水处理和3期分期播种的对比试验,在浇底水前、播种、收获和每旬未每区用土钻法取1 m深土样,用烘干称重法测定土壤含水率,用对比分析的方法研究同一品种在滴灌、喷灌、漫溉条件下和不同播期玉米需水耗水规律。结果表明,滴灌的土壤水分分布及变化对玉米生长最有利,喷灌次之,漫灌最差。滴灌实产最高,耗水量最小,水分利用效率最高,产量次高耗水最少的第三期玉米用水效率最高。滴灌在保证玉米需水的前提下储水能力最强,是干旱缺水地区的高效灌水方式。晚播、晚熟玉米品种有更好、更大的生产潜力和可推广性,就水热匹配来看晚播、晚熟玉米品种也是提高水分利用效率的一种途径。滴灌平均实产较喷灌增加1.69%,较漫灌增加6.53%,耗水量较喷灌减少2.9%,较漫灌减少16.1%,水分利用效率较喷灌增大4.7%,较漫灌增大26.9%,第三期平均实产较第一期增加2.76%,较第二期减少2.81%,耗水量较第一期减少18.2%,较第二期减少18.3%,水分利用效率较第一期增大25.6%,较第二期增大19%。     

Effects of Temperature and Photoperiod on Days to Flowering, Yield and Yield Components of Lupinus albus (L.) under Field Conditions

A better understanding of the agronomic importance of planting date and the influence of cold temperatures and photoperiod during germination and plant growth may lead to better management strategies for cultivation of the sweet white lupin (Lupinus albus). The effects of planting date (temperature and photoperiod) were determined on the number of days to flowering, yield and yield components of four early to medium and one late sweet white lupin genotype in a field trial at Potchefstroom, South Africa, planted during February 1996 to January 1997. Moisture stress was avoided through regular irrigation. Duration of the developmental phases planting date to emergence, emergence to floral initiation, initiation to first flower, duration of flower and days to physiological and harvest maturity was related to field measurements of temperature and photoperiod. Differences in the main determinants of yield, i.e. seeds per pod, pods per plant, single seed mass (SSM), plant and pod height and yield, were measured. Results showed that both temperature and photoperiod influence the growth and development of the Lupinus albus genotypes ‘Esta’, ‘Hantie’, ‘Tifwhite’, ‘Kiev’ and ‘LAL 186’. Temperature influences include the effect of vernalization at seedling emergence. Minimum grass temperatures under 5 °C at emergence are effective for vernalization. However, after grass temperatures at emergence increased again from June to December, to gether with an increase in the photoperiod length, ‘Tifwhite’ as well as the other genotypes still flowered earlier, confirming that these cultivars are long‐day plants, which is in accordance with controlled‐environment data. Cool vernalizing temperatures thus not only influence obligate vernalization requiring genotypes such as ‘Tifwhite’, but also influence the non‐obligate genotypes studied. Plan‐ting date had a significant influence on pods per plant, single seed mass (SSM) and seed yield. In all trials laterplanting, from June to November, decreased SSM and seed yield. The highest seed yield of 1.5 t ha^?1 was obtained for the 10 June planting date and the lowest average yield of 0.450 t ha^?1 for the 5 November planting date.     

播期和密度对麦茬中粳稻皖稻68生育期和产量形成的影响

研究不同播期和移栽密度试条件下皖稻68的生育期和产量形成的变化情况,结果表明,皖稻68生育期天数随播期的推迟而递减,但推迟到6月14日播种仍可正常成熟;移栽密度对生育期无明显影响。不同播期同期栽插的,随播期推迟产量下降,但因秧龄长短的原因,穗数随播期推迟而增加,每穗粒数、结实率和千粒重递减;增加移栽密度有利于增加穗数而增产。本试验条件下皖稻68作为沿淮麦茬稻栽培,育秧移栽的以5月5日和15日播种,移栽密度为30.0万/hm2和40.0万/hm2产量最高,机插秧以5月25日左右播种为宜,直播稻以6月4日至14日为播种适期。     

不同栽培措施对高粱产量的影响

为了探讨不同栽培措施对不同高粱品种产量的影响,寻求高粱获得高产的最佳栽培模式,本试验以晋杂23号和晋中405为试验品种,在山西省农业科院经济作物研究所的试验田研究了不同密度、施肥量、播期对高粱试验品种产量的影响。结果表明,‘晋杂23号’属丰产型品种,不宜密植;‘晋中405’属密植类型,以群体产量获得高产;随着播期的推迟,‘晋杂23号’和‘晋中405’的产量都呈下降趋势,且差异显著。最佳栽培措施：‘晋杂23号’为225 kg/hm2施肥水平、12万株/hm2密度水平及5月2日的播期;‘晋中405’为225 kg/hm2施肥水平、15万株/hm2密度水平及5月2日的播期。     

黑龙港流域玉米不同生育阶段气象因子对产量性状的影响

明确玉米生长发育不同阶段气象因子与产量的关系,有助于确定区域最适播期。通过调整播期来改变玉米生育期内气候条件,对于抵御阶段性不良气象因子的胁迫并最终实现高产目标有重要意义。本研究以郑单958为试验材料,于2009年至2010年在黑龙港地区中国农业大学吴桥试验站进行分期播种试验,分析产量及产量构成因素与不同阶段气象因子的关系。结果显示: (1)由于年际间气象条件的差异,产量及其构成因素并非简单地随播期变化而变化。(2)在试验设定的高密度条件下,产量提升主要受千粒重的制约,穗粒数次之。(3)产量性状与不同生育阶段的多个气象因子显著相关。穗期、抽雄吐丝阶段的光照条件对穗粒数以及产量有影响;苗期、营养生长阶段气温日较差与产量显著正相关;抽雄吐丝前后的温度条件影响穗粒数;生育期总降水量影响穗粒数和千粒重的提升。该地区在调整播种时间、改进栽培措施时,上述关系应是考虑的重点。生产中可适当早播晚收,选用适宜的中晚熟品种,既可避开生育前期及籽粒形成阶段不利气象因子的影响,又可延长籽粒灌浆时间,充分利用该地区生育后期丰富的光热资源。     

播种期对2个不同类型棉花品种产量和产量构成的影响

 适期播种是棉花丰产的重要措施,品种类型常影响播种期。为确定不同类型棉花品种的适宜播期,采用裂区设计,以品种类型（早发型鲁棉研21号和后发型鲁棉研28号）为主区,播种期（4月上旬早播、4月下旬中播和5月上旬晚播）为副区,于2009—2010年在山东临清研究了品种类型和播种期对棉花产量和产量构成的影响。两年的试验结果表明：品种和播期对棉花产量有显著的互作效应,而且主要是由于铃数和衣分的变化所致;早发型品种4月下旬播种产量最高,比4月中旬播种增产6.3%,5月上旬播种与4月中旬播种产量相当;后发型品种4月中旬播种产量最高,比4月下旬和5月上旬播种分别增产4.8%和12%。在鲁西北棉区地膜覆盖栽培条件下,早发型品种以4月下旬播种为宜,可以适当晚播,直到5月上旬;后发型品种应适当早播,以4月中旬为宜,晚播会显著减产。