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1.
In field experiments conducted over 2 years in Mediterranean conditions, five winter and five spring triticales were evaluated for forage and grain production in the same cropping season. The experiments had two treatments, namely harvesting for grain only, and dual-purpose forage and grain production. In the latter treatment, forage was cut when the first node was detectable (Zadoks' stage 31), without removing the apical meristems. Grain was harvested when ripe (Zadoks' stage 92) in both cut and uncut plots.
Environmental conditions affected grain production and protein content more than forage yield and quality. Winter triticales yielded about 43% more forage than spring types, but after forage removal the spring types yielded about 36% more grain than winter triticales.
Reductions in grain yield after clipping were more pronounced in winter (32%) than in spring (19%) types. Forage crude protein content was significantly higher in the spring types studied (24.6%) than in the winter types (23.5%), the opposite being true for fibre content (20.7 and 21.6% respectively). Grain crude protein content did not differ between grain and dual-purpose treatments, but was higher in the spring triticales (12.8%) than in the winter types (11.9%). There was more variability for the measured traits within the winter triticales studied than within the spring types. 相似文献
Environmental conditions affected grain production and protein content more than forage yield and quality. Winter triticales yielded about 43% more forage than spring types, but after forage removal the spring types yielded about 36% more grain than winter triticales.
Reductions in grain yield after clipping were more pronounced in winter (32%) than in spring (19%) types. Forage crude protein content was significantly higher in the spring types studied (24.6%) than in the winter types (23.5%), the opposite being true for fibre content (20.7 and 21.6% respectively). Grain crude protein content did not differ between grain and dual-purpose treatments, but was higher in the spring triticales (12.8%) than in the winter types (11.9%). There was more variability for the measured traits within the winter triticales studied than within the spring types. 相似文献
2.
C. Royo 《Grass and Forage Science》1997,52(1):63-72
Two field experiments were carried out under irrigation and high fertility in northeastern Spain during 1992 and 1993. Ten triticale genotypes, five of spring growth habit and five winter types, were tested for their suitability for both forage and grain. Forage removal reduced grain yield per plant by about 17%, but did not have any significant effect on plant density, ear density or tiller number per plant. Tiller mortality was greater in winter types (65%) than in spring triticales (25%), but was not affected by cutting. Decreases in grain yield following cutting could be attributed to reductions in the number of grains per spike and kernel weight. Cutting decreased the number of grains per spike by about 9% by reducing the two components, spikelets per head and grains per spikelet. The average spike length was 10·6 cm in the uncut treatment and 10·1 cm in the dual-purpose plots. Cutting reduced thousand kernel weight by about 7% in winter triticales, and around 10% in spring types, both in main spike and in first tiller. The effect of a forage harvest on yield components was in general similar for both types of triticale. Cutting when jointing commenced induced changes in the relative importance of yield components influencing future grain yield. The yield components reduced by cutting were the most important contributors to grain yield after forage removal. 相似文献
3.
《Field Crops Research》1995,44(1):13-24
Water use of barley (Hordeum distichon L.) and triticale (× Triticosecale Wittmack) grown for the dual purpose of forage plus grain as an alternative to traditional grain monoculture (control) was assessed at Granada, southern Spain, in two experiments during three cropping years.No significant differences in seasonal evapotranspiration (ET) and soil water depletion at maturity were found between production targets, irrespective of genotype, sowing date and year. A more efficient use of autumn and winter rainfall explained the higher water use observed in 1989/90 in early sown barley as compared to the normal sowing date.There were differences in water-use efficiency (WUE) between seasons in response to clipping: in 1987/88, clipping increased WUE in both experiments relative to the control, while it either reduced it (genotype experiment) or did not affect it (sowing system experiment) in the two following seasons. The response of WUE to clipping was a consequence of similar, differential responses between years observed in dry matter and grain production.Weather-crop interactions caused variable drought and crop water-use patterns among years, which affected the different responses to clipping observed among years. In 1987/88, the crops experienced a prolonged drought period that started around clipping, and increased in severity until anthesis, when spring rains improved growth conditions for some weeks. Forage removal decreased water use and reduced plant water deficit, therefore allowing for enhanced growth and increased water use around anthesis. Thus, clipped cereals had higher grain numbers, dry matter and grain yield than the control at harvest. However, the water-use partitioning observed in the clipping-anthesis period of 1987/88 did not occur in following two seasons. This was possibly due to higher soil evaporation losses after forage removal for clipped cereals in 1988/89, and higher water availability in the clipping-anthesis period in 1989/90. Thus, clipping, by reducing the photosynthetic surface after forage removal, yielded less biomass and grain, and resulted in lower WUE, relative to the control.Winter forage production was associated to ET in 1987/88 and 1989/90, and to WUE in 1988/89 and 1989/90, during the crop phases prior to clipping. However, the increases in ET did not imply lower water availability for subsequent crop phases, as it was the result of more efficient use of autumn and winter rainfall. 相似文献
4.
为了解返青期断根对黄土高原旱地保护性耕作下小麦产量形成及水分利用的调控作用,在陕西长武县开展旱地秸秆覆盖条件下冬小麦返青期断根试验,分析了返青期断根对冬小麦籽粒产量、地上部生物量、收获指数、产量构成三要素、拔节期群体数量、生育期耗水量、水分利用效率、花后旗叶光合特性及衰老特性的影响。结果表明,返青期断根对冬小麦地上部生物量、穗数、粒重和生育期耗水量没有显著影响。与CK(不断根)相比,返青期断根后冬小麦拔节期总茎数减少了11.9%,开花期叶面积指数、花后旗叶叶绿素含量、光合速率和蒸腾速率提高,分蘖成穗率、穗粒数、籽粒产量、收获指数和水分利用效率分别增加了14.1%、10.5%、8.2%、10.4%、17.5%和20.4%。这说明返青期断根可促进秸秆覆盖条件下冬小麦分蘖成穗,增加花后旗叶光合作用,改善穗部结实特性,提高籽粒产量和水分高效利用。 相似文献
5.
小麦氮素高效利用基因型的农艺性状及生理特性 总被引：2，自引：0，他引：2
为给小麦氮高效型品种选育和栽培调控提供理论依据,采用大田试验,以14份小麦品种为材料,研究了不同氮效率品种的农艺性状及生理特性的差异。结果表明,不同小麦品种间产量和氮素利用效率具有显著差异。基于氮肥吸收效率和氮肥农学效率将参试材料分为氮高效型、中效型和低效型。与氮中效型和低效型品种相比,氮高效型品种具有较高的产量、干物质和氮素积累量;在农艺性状上,氮高效型品种具有较高的粒重、收获指数(HI)、叶面积指数(LAI)和开花期旗叶面积;在生理上,氮高效型品种开花期旗叶的叶绿素含量、氮含量、净光合速率、硝酸还原酶活性和谷氨酰胺合成酶活性较高,而成熟期旗叶氮含量较低。聚类分析表明,淮麦30、徐麦32、矮抗58和扬麦16为氮高效型品种。经相关分析,小麦粒重、HI、LAI和开花期旗叶的面积、叶绿素含量、氮含量与氮效率呈显著正相关,小麦成熟期旗叶氮含量与氮效率呈显著负相关,这些指标可作为氮高效型小麦品种筛选的依据。 相似文献
6.
为了解不同类型小黑麦冠层结构及产量构成差异,以加工型品种东农8809、饲用型品种东农5305和粮饲兼用型品种东农96026为材料,采用随机区组设计,探讨了三种类型小黑麦主要生育阶段的平均叶倾角、天空散射辐射透过率、太阳直射辐射透过率、消光系数和叶面积指数的特点。结果表明,加工型品种东农8809的消光系数小,生育后期叶倾角过大,出现漏光现象,这种不合理的冠层结构造成太阳辐射的浪费,使籽粒产量形成受到限制;饲用型品种东农5303的平均叶倾角在营养生长阶段最大,孕穗期降低,营养生长阶段较合理的冠层结构成为其较高叶面积指数形成的基础;粮饲兼用型品种东农96026的平均叶倾角、天空散射辐射透过率和直接辐射透过率均小,消光系数大,冠层结构合理,对光的截获能力强,籽粒产量最高。 相似文献
7.
灌水模式对春小麦光合性能和干物质生产的影响 总被引：1，自引：0，他引：1
为探寻宁夏引黄灌区春小麦节水栽培的适宜灌水模式,比较分析了6个不同灌水处理(W1:二棱水+开花水;W2:二棱水;W3:拔节水;W4:二棱水+孕穗水;W5:二棱水+拔节水+孕穗水+开花水+灌浆水;W6:二棱水+拔节水+孕穗水+开花水)下春小麦光合性能、物质积累与转运、产量性状及水分利用的差异。结果表明,灌二棱水、孕穗水或开花水的W1、W4、W5、W6处理明显增加春小麦花后旗叶光合速率、蒸腾速率和气孔导度,灌二棱水和生育后期少灌水的W1、W2、W4处理明显增加花后旗叶胞间CO2浓度。灌水次数减少会显著增加旗叶SPAD值,并降低叶面积系数,其中以缺少二棱水的W3处理最为明显。灌有二棱水和孕穗水的W4处理明显降低抽穗至开花旗叶SPAD值,增加开花至灌浆旗叶SPAD值和抽穗至开花叶面积系数,灌开花水明显增加开花至灌浆旗叶面积。灌二棱水、拔节水、孕穗水、开花水明显促进了干物质积累,灌水次数增加明显增加了叶干物质积累量,并降低茎鞘干物质比例;缺少二棱水的W3处理最不利于叶、穗干物质积累,但提高了开花至成熟叶干物质比例;灌浆水对各器官干物质积累影响不明显。二棱期至开花期缺少灌水的W1、W3、W2处理促进了开花前贮藏同化物在花后向籽粒的转运。籽粒产量随灌水次数的增加而增加;缺少二棱水明显降低穗粒数、收获指数,但增加千粒重;增加灌水次数降低了灌水利用效率,且以灌二棱水影响最为明显。综上所述,缺少二棱水对春小麦产量影响最明显,孕穗水、开花水影响次之,灌浆水影响不明显。 相似文献
8.
为给长江中下游地区小麦高产耐渍品种选用提供参考,以小麦品种扬麦25、扬麦24、宁麦13和宁麦9号为材料,分析了孕穗期连续10 d渍水处理对小麦叶面积和光合速率、地上部干物质积累、籽粒产量及其结构和不同土层（0~100 cm）根系干重的影响。结果表明,与对照（正常水分）相比,渍水处理显著降低小麦籽粒产量,降幅12%~31%,穗粒数和千粒重的减少是减产的主要原因。相比其他品种,渍水后扬麦25产量降幅小,产量构成较协调,受渍水影响轻。渍水处理显著减少小麦开花期和成熟期不同土层根系干重,其中对下层根系的影响大于上层根系;渍水也显著降低乳熟期倒三叶面积、倒二叶和倒三叶净光合速率,明显抑制成熟期地上部各器官和花后光合物质积累。在对照条件下,扬麦25的根系干重在开花期与其他品种相近,成熟期的0~20和80~100 cm土层根系干重则较高;在渍水条件下,扬麦25能在花后维持较高的上层根系生物量,成熟期的0~60 cm土层根干重占总根干重比例较高。不同水分处理下,扬麦25均具有面积大的旗叶且高的净光合速率,花后维持较久的上三叶绿色面积和积累更多的光合产物。因此,小麦花后根系生物量保持稳定（尤其是表层根系）,绿叶面积较大且衰减慢（尤其是旗叶）,有助于增强小麦花后光合物质积累能力,促进籽粒灌浆和单穗高产稳产,这可作为高产耐渍品种的筛选依据。 相似文献
9.
为探明不同幅宽条播和覆膜穴播对河套灌区有机春小麦的产量、开花期农艺性状、杂草发生程度及经济效益的影响,设置覆膜穴播（FM）、宽幅16 cm条播（KF16）、宽幅7 cm条播（KF7）、窄幅窄行11 cm条播（ZF11）、窄幅宽行15 cm条播（ZF15）共5种不同播种方式,研究了不同处理下有机小麦开花期农艺性状、籽粒产量、杂草密度及各生育时期杂草干物质量和经济效益的差异。结果表明,与ZF15处理相比,FM处理显著提高了有机小麦开花期株高、旗叶长、旗叶面积、单株叶面积、旗叶SPAD值,KF16处理明显改善了旗叶光合速率,而KF7和ZF11处理的叶面积指数显著低于其他处理;FM、KF16、ZF11、KF7处理的籽粒产量较ZF15处理分别提高了33.0%、27.2%、21.5%、14.9%;KF16和FM处理的杂草总密度和杂草干物质量较ZF15降低了 75.6%、92.8%和73.9%、81.4%,纯收益分别增加了7 680.4元·hm-2和7 246.7元·hm-2。经相关分析,杂草干物质量与有机小麦产量呈显著或极显著负相关。综上所述,宽幅16 cm条播和覆膜穴播可有效降低杂草密度及干物质量,促进小麦生长发育,提高有机小麦籽粒产量。 相似文献
10.
冬春季夜间增温对冬小麦植株氮代谢和籽粒蛋白质形成的影响 总被引：1，自引：0，他引：1
为明确非对称性增温对小麦籽粒品质的影响及其机理,以不同品质类型的扬麦13（弱筋）和烟农19（中筋）为材料,采用大田模拟增温的方法研究了冬春季夜间增温对小麦籽粒蛋白质形成的影响及其与植株氮代谢的关系。结果表明,冬季增温（WT）、春季增温（ST）及冬春季持续增温（WST）均不同程度地提高了冬小麦籽粒蛋白质、麦谷蛋白大聚合体（GMP）、高分子量和低分子量麦谷蛋白亚基含量,且均以WST处理效应最大。同时,各增温处理对籽粒谷蛋白含量的提高幅度最大,并提高了谷醇比。各夜间增温处理均增加了开花期旗叶面积,提高了氮含量,增强了孕穗至花后21 d旗叶的硝酸还原酶（NR）、谷氨酰胺合成酶（GS）活性,说明夜间增温促进了叶片生长,增强了植株氮素同化能力。夜间增温处理显著提高了小麦植株氮素积累量及贮存氮素转运量,从而增加了氮素向籽粒的分配,促进了籽粒蛋白质合成。因此,冬春季夜间增温提高了小麦氮素吸收同化能力及氮素在籽粒中的分配比例,从而提高小麦籽粒蛋白质含量,且冬春季持续增温对籽粒蛋白质形成有更大的促进效应。 相似文献
11.
In field experiments conducted over 2 years, triticale was compared with barley, bread wheat and oats for its dual-purpose (forage and grain) capability.
The effect of spring forage removal on grain yield ranged from small yield increases (in the triticale and barley genotypes that otherwise lodged) to a 53% decrease, and was dependent on species, genotype, stage of development when cut, and time for recovery before grain harvest. A key factor influencing grain yield after early cutting was the number of spikes that developed.
The complete types of triticale were better than the one substituted type tested for dual purpose but, as there is variability among them, selection for good mixed aptitude is possible.
The production of the best triticale averaged over 2 years 3 t of forage DM ha-1 (with 684 kg of crude protein ha-1 ) and then 4–3 t of grain ha-1 . In this instance, neither the grain yield nor the number of spikes per plant were reduced after clipping, in spite of the fact that the shoot apices were removed.
Plant height and lodging were reduced by a forage cut. In triticale, the number of days to heading was increased even more when the cut was late, but no effect was observed in barley. 相似文献
The effect of spring forage removal on grain yield ranged from small yield increases (in the triticale and barley genotypes that otherwise lodged) to a 53% decrease, and was dependent on species, genotype, stage of development when cut, and time for recovery before grain harvest. A key factor influencing grain yield after early cutting was the number of spikes that developed.
The complete types of triticale were better than the one substituted type tested for dual purpose but, as there is variability among them, selection for good mixed aptitude is possible.
The production of the best triticale averaged over 2 years 3 t of forage DM ha
Plant height and lodging were reduced by a forage cut. In triticale, the number of days to heading was increased even more when the cut was late, but no effect was observed in barley. 相似文献
12.
不同阶段夜间增温对小麦生长特性及产量的影响 总被引：2，自引：0，他引：2
全球变暖表现出夜间增温幅度大于白天的非对称性增温特性,为明确不同阶段夜间增温对小麦生长发育特征及产量的影响,以扬麦18为试验材料,采用被动式增温装置分别对小麦分蘖期至拔节期(NW_(T-J))、拔节期至孕穗期(NW_(J-B))、孕穗期至开花期(NW_(B-A))三个不同阶段进行夜间增温处理,以不增温为对照(NN),研究不同阶段夜间增温对小麦生长发育特性、旗叶衰老特性及产量的影响。结果表明,不同阶段夜间增温均能提高小麦花后0～15 d旗叶面积和叶绿素含量;显著提高灌浆前期小麦旗叶的超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性,降低花后0～15 d小麦旗叶丙二醛(MDA)含量;显著增加成熟期小麦干物质的积累量,提高小麦产量,其中,NW_(J-B)处理下小麦产量增加幅度最大,较NN(对照)提高了8.75%。本试验条件下,拔节期至孕穗期夜间增温提高了花后0～15 d小麦旗叶面积、叶绿素含量和抗氧化酶活性,降低了灌浆前期小麦旗叶膜脂过氧化程度,最终增加了小麦的干物质积累量和产量。 相似文献
13.
源库调节对小麦籽粒灌浆及光合特性的影响 总被引：6，自引：2，他引：6
为探讨不同穗型超高产小麦品种的源库关系，通过剪叶和去穗处理研究了两个不同穗型小麦品种“兰考矮早八”和“豫麦49—198”的籽粒灌浆和光合特性。结果表明，两个品种的籽粒体积、千粒重、灌浆速率在花后15d之后均表现为去穗处理〉对照〉去叶处理。去叶处理使两个品种的千粒重、灌浆速率均有所下降．其中豫麦49—198较对照下降最大比例分别为24．4％和22％，兰考矮早八下降的最大比例分别为7．6％和9％；去穗处理使两个品种的千粒重和灌浆速率均有所增加，其中豫麦49—198较对照增加的最大比例分别为11．1％和17％，兰考矮早八增加的最大比例分别为12．2％和17．25％。源库改变对两个品种的光合特性均有影响，表现为对照旗叶〉去穗旗叶〉去叶倒二叶〉对照例二叶。随着灌浆进程，豫麦49—198去叶处理的倒二叶光舍速率较对照增加的比例从40％减为25％．兰考矮早八去穗处理的旗叶光合速率较对照下降的比例从27％减为20％。 相似文献
14.
不同类型小黑麦饲草产量和品质特性研究 总被引：1，自引：0，他引：1
在江苏生态条件下研究不同类型(饲草型、粮饲兼用型和粮用型)小黑麦品种饲草产量和品质特性,结果表明:①不同类型小黑麦随生育进程推移,植株鲜草产量和干草产量逐步上升,鲜草产量多数品种在开花达最大值,少数品种在孕穗期或籽粒形成期达最大值,干重产量至灌浆期或成熟期达最大值,品种间和类型间存在差异。②小黑麦冬前或籽粒形成期割青,鲜草产量显著高于大麦,在拔节期至开花期收割,产量相差较小。③不同类型小黑麦植株蛋白质含量开花之前呈下降趋势变化,积累量呈"S"型曲线变化,整个生育期植株蛋白质含量高于对照大麦品种,粮饲兼用型品种各生育期蛋白质积累量均高于对照。植株中性洗涤纤维含量随生育期推移呈先上升再下降或一直上升的变化趋势,积累量亦呈"S"型曲线关系。植株可溶性总糖含量随生育进程呈一直下降的变化趋势。④综合产量和品质表现,不同类型小黑麦饲用的价值存在差异,粮饲兼用型品种中饲237可于拔节期至孕穗期割青作青或干饲料;饲草型品种OH1881在越冬期、开花期收割作青或干饲料。 相似文献
15.
冬小麦叶茎粒可溶性糖含量变化及其与籽粒淀粉积累的关系 总被引：41，自引：10，他引：41
在池栽条件下研究了鲁麦22和鲁麦14两个冬小麦品种旗中、倒二茎、籽粒糖含量及籽粒淀粉积累速率的变化。结果表明，小麦叶片可溶性糖和蔗糖含量在开花后15－20d出现高峰；茎可溶性总糖、蔗糖和果聚糖含量变化呈单峰曲线，最高含量亦出现在花后15－20d，而籽粒可溶性总糖和蔗糖含量在灌浆期呈下降趋势，花后20d至成熟期各器官糖含量与籽粒淀粉积累密切相关。 相似文献
16.
全球变暖表现出夜间增温幅度大于白天的非对称性增温特点,小麦作为温凉型作物,产量和生理特性易受非对称性增温的影响。为探究花前夜间增温对冬小麦光合特性及产最形成的影响,以春性品种扬麦18和半冬性品种烟农19为试验材料,采用大田盆栽方式,利用被动式增温装置分别在分蘖期至拔节期(WT-J)、拔节期至孕穗期(WJ-B)、孕穗期至开花期(WB-A)三个时间段进行夜间增温处理,以不增温为对照(CK),分析经过三个花前不同时段夜间增温后小麦旗叶光合特性及产量特性的变化。结果表明,花前夜间增温使小麦旗叶灌浆期的净光合速率、蒸腾速率、气孔导度和胞间CO2浓度均有所增加,WT-J、WJ-B处理均提高了冬小麦旗叶面积、最大光化学效率和实际光化学效率,同时使旗叶气孔密度和气孔指数较CK分别增加了12.64%、8.45%和10.21%、7.56%。扬麦18、烟农19的可孕小穗数在WT-J处理下较CK分别提高了9.01%和5.25%。扬麦18开花期干物质积累量在WT-J和WJ-B处理下较CK分别提高了13.18%和10.23%,烟农19在WT-J和WJ-B处理下较CK分别提高了16.21%和1... 相似文献
17.
A.J. de la Vega M.A. CantoreM.M. Sposaro N. TrápaniM. López Pereira A.J. Hall 《Field Crops Research》2011,121(1):175-185
Delayed leaf senescence during the grain filling phase, or stay green (SG), may be functional or cosmetic; the first being considered a valuable trait in breeding of many crop species. To establish whether canopy senescence patterns exhibited by two sunflower (Helianthus annuus L.) hybrids visually selected for slow post-anthesis canopy leaf area index (LAI) loss reflected functional, rather than cosmetic, SG, LAI dynamics and total biomass increase between anthesis and physiological maturity were followed in three separate experiments in which the putative SG hybrids were compared with standard (i.e., non stay green, NSG) hybrids exhibiting normal rates of canopy senescence under non- or minimal-water stress conditions. In two experiments, pairwise (i.e., one SG vs. one NSG) comparisons were made at two crop population densities. In the third experiment, grown at a single crop population density, four NSG hybrids were contrasted with the two SG hybrids. Canopy senescence dynamics were well described by fitted bilinear functions which discriminated between an initial, slow phase of leaf area loss and a second phase of rapid canopy senescence. No differences between hybrids in the rate of senescence during the first phase were found, but the putative SG hybrids exhibited a significantly slower rate of senescence during the second phase and a significantly higher LAI at physiological maturity (as % of LAI at anthesis). One NSG hybrid showed a greater rate of second-phase senescence than the remaining three hybrids in this category. Across experiments, the anthesis-physiological maturity increment in total oil-corrected biomass and radiation use efficiency (RUE) were significantly greater in the SG hybrids. Cluster analysis based on these four attributes, using data from Exp. 3, clearly discriminated between SG and NSG hybrids. Examination of specific leaf N (SLN) dynamics suggests that the lower RUE values observed in one of the NSG hybrids could be attributable to lower SLN values, but this was not the case for the remaining NSG hybrids. It is also possible that very rapid canopy LAI loss in another NSG hybrid may underlie its lower RUE. The failure of SG hybrids to translate greater post-anthesis biomass increment into grain yield across experiments was associated with their slightly shorter times to anthesis and their significantly lower biomass at anthesis. Grain number, the component of yield most strongly associated with yield, was associated with biomass at anthesis. A further contributing factor was that the duration of grain-filling tended to be shorter in SG hybrids. In the one experiment in which this variable was measured, resistance to stalk breakage was greater in the SG hybrids than the NSG one to which they were compared. We conclude that the SG observed in the hybrids with slower canopy senescence is functional and not cosmetic, and that for this to be translated into a yield advantage all hybrids need to reach anthesis at the same time and grain-filling duration also has to be the same across hybrids. Stay green is an interesting secondary trait to select for and should lead to higher and more stable yields in environments in which stem breakage (lodging) is a problem. 相似文献
18.
《Field Crops Research》1995,44(1):1-11
In many rainfed regions of Euro-Mediterranean countries, current political and socio-economic developments demand research in alternative production systems to the common cereal grain monoculture. We studied the option of producing forage in winter by growing cereals for dual purpose (forage plus grain) in a Mediterranean environment. The effect of clipping on forage and grain production was assessed between 1987 and 1990 at Granada, southern Spain, in four cereal cultivars, and in one barley cultivar under three sowing systems.Winter forage yield of cereals, all clipped once at the stage of lemma primordia, was highly variable (25 to 311 g m−2 of herbage dry matter), with considerable differences among cultivars, sowing systems and seasons. Treatments that had higher forage production were those of either longer crop duration before clipping date (with higher leaf numbers on the main stem and tiller numbers per plant) or higher plant density. Forage production was not related to grain yield reductions due to winter clipping.Averaged over cultivars, sowing systems and seasons, clipping reduced grain yield by 1%, but yielded some 127 g m−2 of dry matter per season in a period of pasture shortage. Nevertheless, the responses to winter clipping differed among seasons. In 1987/88, clipped cereals produced more dry matter and grain than the control. In contrast, in the last two seasons, clipping reduced dry matter and grain production. Early sowing modified the response to clipping in these last two seasons. Grain yield of early sown barley was not reduced by clipping in 1988/89 and was even increased in 1989/90.The dual-purpose target for cereals could be an alternative to traditional grain monoculture in some Mediterranean environments, provided that adaptations of the traditional crop management to dual purpose, such as the optimization of sowing date and cultivar, are undertaken. 相似文献
19.
This study was conducted to determine effects and interactions of plant density on digestibility and plant morphology of diverse orchardgrass ( Dactylis glomerata L.) clones. Propagules of ten orchardgrass clones with contrasting morphology from two maturity groups (inflorescence emergence differed by 8d) were evaluated in sward (0·15-m centres) and spaced (0·60-m centres) plantings. Plants were harvested from spring growth on a common date near anthesis and from summer growth when about 5 weeks of forage growth had accumulated. The plants were separated into morphological parts before measuring their size and in vitro digestible dry matter (IVDDM). There were few plant density × orchardgrass clone interactions, and correlation coefficients of clones grown at the two plant densities generally were high (e.g. 0·87 in spring and 0·67 in summer for IVDDM of total herbage). Plant density had little effect on morphology of leaf blades from reproductive tillers, but leaf blades of vegetative tillers were 12% (spring) and 22% (summer) longer from sward than from spaced plantings. Moreover, reproductive tillers were 26% taller in sward than in spaced plantings. Also, leaf blades of vegetative tillers in spring growth were more than twice as long, of similar width and 65% thicker than leaf blades from reproductive tillers. Because divergent genotypes respond similarly to plant density, it is concluded that observations taken in spaced plantings of orchardgrass can be used to make inferences about relative differences in sward plantings for the traits studied. 相似文献
20.
氮肥不同施入量对水稻新品种富友33生育及产量的影响 总被引：1，自引：0，他引：1
采用小区对比试验方法,探讨了氮肥不同施入量对水稻新品种富友33生育及产量的影响。结果表明,增加氮肥施入量,可促进富友33单位面积收获穗数、齐穗期叶面积指数与剑叶净光合速率、成熟期干物质积累量的增加;不利于其成穗率、齐穗期高效叶面积率与有效叶面积率、齐穗后干物质积累量占籽粒产量百分比以及收获指数的提高。在本试验条件下,施氮量(N)240.0 kg/hm2的处理E3获得单产9.22 t/hm2,比E4、E2、E5、E1处理分别增产了0.2%、3.1%、3.4%和7.3%。 相似文献