Irrigation Regimes on Utilization of Nutrients, Yield and Quality of Sugarcane (Saccharum officinarum L.)

With a view to study the influence of irrigation regimes at critical stages of sugarcane an investigation was carried out at Agricultural Research Station, Tamil Nadu Agricultural University, Bhavanisagar, India during Mid-late season (March–April) using Co 6304 as test variety. Treatments consisted of eight irrigation regimes created by imposing two levels of irrigation 0.75 and 0.5 IW/CPE ratio at critical stages (tillering, grand growth and maturity). The results revealed that irrigating sugarcane at 0.75 IW/CPE ratio at tillering and growth and 0.5 IW/CPE at maturity phase recorded highest nutrient uptake, cane yield (139 t/ha) with 10.6 % CCS consuming 1791 mm of water the highest water use efficiency of 77.3 kg/ha mm.     

甘蔗不同熟期品种合理搭配与提高蔗糖分关系的研究

根据甘蔗不同熟期品种蔗糖分积累变化和高糖期出现迟早早存在差异的特点,应用其积累动态模拟模型,探讨不同品种搭配形式与提高蔗糖分的关系,从理论上阐明早,中,迟熟品种合理搭地延长高糖期和提高蔗糖分的作用,并给出品种搭配求算原则和方法,为糖厂确定不同期品种的种植比例,提高经济效率提供指导依据。     

Root Yield and Quality of Sugar Beet (Beta vulgaris L.) in Relation to Plant Population

Introduction of genetic monogerm seed and the advancement of agricultural techniques raised the possibility of eliminating costly thinning operations in sugar beet farming. However, this requires high and uniform seedling emergence to provide prerequisite plant populations in the field. This work investigated the minimum levels of seedling emergence for non-thinned sugar beet farming. The experiment was carried out in a loamy soil to investigate the effects of three levels of emergence (60, 50 and 35%) and two intra-row spacings (8 and 15cm) with or without thinning using seed source of graded viability of cv Eva in 1992 and 1993 under field conditions in Eastern Anatolia. Plant population throughout the growing period was monitored and data were taken of yield and quality parameters. On average, 60, 50 and 35% emergence levels were achieved using seed source of 90, 72 and 54% viability range, which resulted in different levels of plant stands depending on intra-row spacing and thinning. Plant density at harvest ranged between 49 500 and 124 500 ha⁻¹ on average depending on initial establishment, intra-row spacing and thinning. Root yield and sugar yield were the highest at plant stands between 90 000 and 100 000 ha⁻¹, below or above of which declined. Impurity contents (e.g. Na, K and a-amino N contents) and extractable sugar content decreased but sugar content and clear juice purity enhanced as plant stands at harvest increased.     

内生真菌对甜菜主要农艺性状及氮糖代谢关键酶活性的影响

采用内生真菌F11液浸种、喷叶及灌根处理方法,调查其对甜菜栽培品种KWS2409的主要农艺性状及对甜菜氮、糖代谢关键酶即硝酸还原酶(NR)、谷氨酰胺合成酶(GS)、蔗糖合酶(SS)和蔗糖磷酸合酶(SPS)活性的影响。结果表明,内生真菌F11菌株对甜菜的含糖量有明显的提高作用,其中以灌根处理效果最好,其叶鲜重、叶绿素含量、单根重、含糖率和产糖量的平均值分别提高了66.67%、47.42%、6.96%、17.46%和25.63%。在整个生育期,内生真菌F11显著提高了氮糖代谢酶活性,其中NR和GS活力分别呈“M”型双峰曲线和抛物线型变化,而SS和GS活力呈单峰曲线变化,后期根部SS合成活力明显高于分解方向活力,生育前期SPS活力高于后期。叶丛形成期达到最高峰,说明NR、GS、SS和SPS活性的增强是甜菜含糖量升高的主要生理原因。     

Performance of Sugarcane (Saccharum officinarum L.) Under Surface Drip, Sub Surface Drip (Biwall) and Furrow Methods of Irrigation

Field experiments were conducted at the Sugarcane Breeding Institute, Coimbatore, India during 1989–93 to study the productivity and water use efficiency of sugarcane under different methods of irrigation. The results showed that there could be a 44 % saving in water with higher water use efficiency in drip irrigation compared to conventional furrow irrigation. Among drip irrigation systems in the plant crop, sub surface drip (Biwall) at 40/140 cm spacing recorded a significantly higher number of millable canes, cane length and single cane weight compared to either conventional furrow irrigation or furrow irrigation based on IW/CPE (Irrigation Water Cumulative Pan Evaporation) ratio. In ratoon crop, Biwall irrigation at 60/120 cm gave significantly higher cane length and single cane weight compared to any other methods of irrigation. However, cane and sugar yields in Biwall irrigations were on par with conventional furrow irrigation but superior to either surface drip or furrow irrigation based in IW/CPE ratio.     

甜菜各叶片对块根增长、根内糖分积累作用的研究

本文揭示了甜菜各叶片对块根增长、根内糖分积累的贡献。甜菜子叶和第1-10片叶的同化产物主要供给幼苗根系和叶片的生长,为甜菜的生长奠定了基础。甜菜的第11-35片叶的功能盛期处在块根增长期和糖分积累期,对块根增长和根内糖分积累起主要作用,各叶片对块根增长的贡献顺序：第11-15片叶＞第16-20片叶＞第21-25片叶＞第26-3     

氮素形态对甜菜氮糖代谢关键酶活性及相关产物的影响

用营养液培养的方法, 以甜研7号为试验材料, 研究了同一氮素水平不同氮素形态比例对甜菜氮、糖代谢关键酶: 硝酸还原酶(NR)、谷氨酰胺合成酶(GS)和蔗糖合成酶(SS)活性及相关产物的影响. 结果表明叶片中NR活性随NO-3比例增加而增加; 根和叶片中GS活性, 当NH+4小于NO-3时, 随NH+4比例增大而增加, 当NO-3∶NH+4为1∶     

Effect of Zinc and Iron Supply on Production Potential of Rice (Oryza sativa L.)

A field experiment was performed to study the effect of zinc and iron supply on grain yield in four promising varieties of rice ( Oryza sativa L.) viz. IR-20, Jaya, Pusa 2–21, and IET-1444. Three doses of ZnSO₄ or FeSO₄ (0, 20 or 40 kg ha⁻¹) along with all possible combinations were investigated. The varietal differences were significant in grain yield ha⁻¹. The grain yield increased with the dose of zinc and Jaya but not significantly in IR-20. The increase in grain yield was more significant and dose dependent in IET-1444 than in Jaya in response to iron application.     

Effects of Partial Defoliation on Sucrose Accumulation, Enzyme Activity and Agronomic Parameters in Sugar cane (Saccharum spp.)

Mechanical defoliation of sugar cane plants (Saccharum spp.) will provide leaves that can be used as fodder. The effect of partial mechanical defoliation on sucrose content, enzyme activities and agronomic parameters of sugar cane is still unknown. We investigated how sucrose accumulation, activities of sucrose phosphate synthase, soluble acid invertase, sucrose synthase, neutral invertase, brix grades, purity grade, moisture content, fibre content, maturity index and reduced sugars of two commercial sugar cane plants (Mex 69‐290 and Mex 57‐473) were affected in a field experiment. The concentration of sucrose in stems of partial defoliated plants was not significantly different from that found in intact plants. Agronomic parameters and enzyme activities were not different in defoliated plants compared with intact plants except for the moisture content which was higher in defoliated plants than in intact ones. These results indicated that sugar cane plants could be partially defoliated without changing sucrose production and agronomic parameters while providing leaves that could be used as fodder.     

Studies on the Effect of Moisture Stress at Different Growth Phases on Seed Vigour, Viability and Storability in Peanut (Arachis hypogaea L.)

Studies were conducted on the influence of moisture stress at different growth phases, either alone or in combination, on seed yield, quality and longevity in groundnut, at Agricultural College and Research Institute, Coimbatore. At the end of each growth phase, irrespective of available soil moisture, plots were irrigated with a measured quantity of water to a depth of 5 cm, sufficient to raise the soil moisture content of top 30 cm layer to field capacity. Plots which received stress were not irrigated in the respective growth phases. Moisture stress during the combined reproductive phases, viz. flowering + pegging and pegging + maturity, had a mitigating influence on growth and yield to a greater extent than stress at other phases. Though water deficit at different growth phases had no impact on viability and vigour of fresh seeds, it helped to enhance the longevity and the greater the stress the better the storability. The conversion of oil into free fatty acids was least in seeds collected from stress. Membrane integrity as indicated by electrical conductivity and leachate amino acids were also minimal in seeds from stressed plots.     

蛋白和核酸合抑制剂对氮素诱导甜菜谷氨酰胺合成酶基因表达的影响

谷氨酰胺合成酶(GS)家族是甜菜等高等植物体内氨态氮同化酶, 也是氮利用与循环的核心构件。为了揭示在氮素诱导下, 放线菌素D(AMD)和放线菌酮(CHM)对甜菜GS基因调控表达的影响。采用半定量RT-PCR技术, 对甜菜的胞液型谷氨酰胺合成酶基因(GS1)和质体型谷氨酰胺合成酶基因(GS2)进行mRNA的表达检测, 同时进行GS活性的测定。结果表明, 甜菜幼苗经过低浓度AMD处理2~6 h, GS活性略有增加, 9 h后, 高和低浓度AMD处理下的GS活性都下降, 且随着浓度的增加下降幅度加大, 同时GS1mRNA和GS2mRNA的相对量随浓度的增加而下降。CHM处理甜菜幼苗9 h后, 随着浓度的增加和处理时间的延长, GS活性下降幅度增加, 但GS1mRNA和GS2mRNA的相对量在不同CHM浓度处理间变化不显著。     

苗期遮光及光照转换对不同玉米杂交种光合效率的影响

研究了苗期遮光及光照转换对两个玉米杂交种叶片光合速率、荧光特性的影响。结果表明,遮光条件下叶片叶绿素含量,尤其是叶绿素a的含量下降,光合速率(Pn)降低,但遮光后叶绿素含量和叶绿素a/b值的下降幅度均表现为杂交种掖单22小于丹玉13。与此相同,遮光使丹玉13 Pn的下降显著大于掖单22。由遮光转入自然光下后Pn迅速下降     

大葱生长发育过程中可溶性糖、可溶性蛋白质及游离氨基酸含量变化规律的研究

研究了大葱生长发育过程中可溶性糖、可溶性蛋白、游离氨基酸含量变化动态。结果显示,随着大葱的生长,可溶性糖呈现低-高-低-高的变化规律,但不同材料的变化有差异。日本品种假茎可溶性糖含量变化幅度不大。而地方品种胭脂红、托县孤葱在采收时假茎中可溶性糖含量较高。假茎蛋白质含量表现为高-低-低-高的趋势。定植30 d后假茎蛋白质含量最高,以后随着生长、发育,蛋白质含量逐步下降;到采收期假茎内蛋白质含量又在积累,葱叶中蛋白质含量变化与假茎相似。大部分材料定植后随着大葱的生长发育,假茎中游离氨基酸含量呈上升趋势,近采收期达到最大值。不同材料葱叶中游离氨基酸含量不同,随着生长发育呈现低-高-低-高的变化趋势,葱叶中游离氨基酸含量远远低于假茎。     

不同种植密度对甜高粱糖分积累及SS、SPS活性的影响

对甜高粱2个品种XT-2、T601设置7个不同种植密度处理,分析了甜高粱不同生育阶段总糖含量、还原糖含量、蔗糖含量、SS和SPS活性的变化。2个品种的总糖含量随生长进程均升高,成熟期达最高值。其还原糖的变化趋势不一致,XT-2呈升高-平缓-降低的趋势,T601呈升高-降低的趋势。2个品种在整个生育期蔗糖含量均呈升高的趋势,成熟期达最高值。T601除密度处理B6 (6170株 hm^–2)外其他处理SS活性均呈升高-降低-升高的趋势,XT-2无明显规律。XT-2除密度处理B2 (11 110株 hm^–2)、B4 (7929株 hm^–2)外其他处理SPS活性均呈升高-降低-升高的趋势,T601无明显规律。综上所述,甜高粱品种XT-2最适于糖分积累的密度为9250 株 hm^–2,成熟期总糖含量达14.2% (鲜基),T601的最适密度为11 110株 hm–2,成熟期总糖含量达14.31%(鲜基),作为积累糖的原料,后者为最佳选择。完熟期SS活性下降、SPS活性上升有利于糖的积累,为最佳收获时期。     

不同地力水平下控释尿素对玉米物质生产及光合特性的影响

氮肥是玉米生产中最重要的增产要素之一。为探明不同地力水平下控释尿素对玉米物质生产及光合特性的影响, 采用盆栽试验研究了释放期不同的2种控释尿素(CRU₃₀, 释放期为30 d; CRU₆₀, 释放期为60 d)的作用效果, 以普通尿素为对照(U)。结果表明, 控释尿素处理显著增加玉米干物质积累量, 但释放期不同的控释尿素在不同地力水平下增产效果不同, 低地力水平下增产效果为CRU₃₀>CRU₆₀>U (P<0.05), CRU₃₀处理比施用普通尿素增产18.9%; 高地力水平下增产效果为CRU₆₀>CRU₃₀>U(P<0.05), CRU₆₀处理比U增产18.2%。与对照相比, 控释尿素使干物质向开花后分配比例增加, 氮肥偏生产力(PFPN)显著提高, 低地力时CRU₃₀最高, 而高地力时CRU₆₀最高。控释尿素处理的单株干物质积累量、穗粒数及千粒重显著增加, 主要因为生育中后期叶面积、光合速率、叶绿素及叶片氮含量维持较高水平。所以, 在等氮量做基肥一次性施入时, 低地力水平下施用释放期较短的控释尿素为宜, 而高地力水平下应施用释放期较长的控释尿素。     

棉花对硼的吸收、运转和分配的研究

通过水培和土培试验,研究了棉花根系和叶片对硼的吸收、运转和分配。结果表明,根系对硼的吸收、运转速率快于叶片,但叶片施硼能直接满足叶片对硼的需要。棉花叶片对硼的运输随棉花生长时期不同而异:营养生长时期,硼主要运输到生长点和幼嫩叶片中;生殖生长时期,硼主要运输到繁殖器官和为繁殖器官制造养料的主茎叶及其相应的果     

Some Effects of Soil Salinity on Growth, Development and Yield of Rapeseed (Brassica napus L.)

The effects of increasing soil-salt levels on emergence, shoot and root growth and yield composition of rapeseed were investigated. A range of electrical conductivity (EC) values in the soil solution from 2.3 dS m^-1 to 10.3 dS m^-1 was obtained by adding NaCl to the substrate. The emergence was significantly (P < 0.05) decreased at EC values higher than 6 dS m^-1 Above this value, a delay in the appearance of leaves and of the first visible internode was observed. The further increase of salinity level extended the period for siliqua formation and grain filling, and plant height, pod number and grain number per plant were lowered. However, the cultivar used showed the ability of counterbalancing for this lower grain number by increasing the seed weight, thus there were no variations on seed yield. The seed oil and protein content were also not affected by the changes in salinity. Root growth was adversely affected when salinity levels exceeded 6 dS m^-1. Beyond this value, short tuber-like roots became remarkably frequent. This may be an adaptation mechanism of this species to saline stress; a similar reaction in rapeseed is known in adaptation to drought stress.     

Growth,Photosynthetic Characteristics,Antioxidant Capacity and Biomass Yield and Quality of Wheat (Triticum aestivum L.) Exposed to LED Light Sources with Different Spectra Combinations

As a consequence of the increasing importance of crop in Bioregenerative Life Support System (BLSS), there is an interest in enhancing both the productivity and quality of wheat. Lighting systems for growing wheat need to be lightweight, reliable and durable. Light‐emitting diodes (LEDs) have these characteristics. Previous studies demonstrated that the combination of red and blue lights was an effective light source for several crops. Yet the appearance of plant in this kind of lighting was purplish grey, and other problems were also accompanied. The addition of other spectra LEDs made better growth and also offer a better visual experience to bring psychological benefit to the crews. The objective of this study was to investigate the influences of different spectra combinations on the wheat growth, photosynthetic characteristics, antioxidant capacity and biomass yield and quality during their life cycle. Four types of different spectra combinations with the same intensity were employed: a single red light (R), a red–blue light (R + B, R : B = 4 : 1), a red–white light (R + W, R : W = 4 : 1) and a white light (W). The results showed that the wheat cultivated in the R + W light was characterized by highest harvest index and lowest lignin in inedible biomass, which was more beneficial to recycle substances in the processes of the environment regeneration. The data were comparable to those under W condition in terms of straw height, relative water content (RWC), membrane stability index (MSI), photosynthetic rate, chlorophyll concentration, antioxidant capacity, thousand kernel weight (TKW) and soluble sugar concentration. Wheat was sensitive to light quality which significantly affected those indices of growth and physiology, especially at earing and flowering stages.     

不同生育期（阶段）有限补灌对小麦产量和水分利用效率及经济效率的影响

为高效利用灌溉水资源,提高灌溉水水分利用效率和水分经济效率,在山西临汾采用随机区组设计方法研究了不同年型各生育期（阶段）有限补灌对产量、水分利用效率及经济效率的影响。结果表明：2个年型（正常和干旱）条件下：各生育阶段灌水处理的平均产量、水分利用效率和灌溉水水分经济效率均表现为冬前灌水>春季灌水>后期灌水;各生育时期灌水处理的平均产量和灌溉水水分经济效率均表现为冬水>孕穗水>拔节水>扬花水>返青水>起身水>灌浆水>对照（不补灌）,水分利用效率为冬水>孕穗水>扬花水>返青水>起身水>拔节水>灌浆水>对照（不补灌）。降雨正常年型各生育阶段灌水处理的平均产量、水分利用效率均高于干旱年型,而干旱年型灌溉水水分经济效率却高于正常年型。此项研究同时明确了各生育期灌水处理的土壤水分动态。该项研究为发展半旱地农业提供了理论和技术支撑。     

土壤干旱对甘薯生育及产量的影响

利用甘薯品种郑红５号和徐薯１８研究了土壤干旱对甘薯生育和产量的影响。结果表明，生长前期（栽后０～６０天）叶片数、叶面积、茎长及其相应的干旱胁迫指数均随土壤干旱程度的加重而相应减少，薯块的形成和膨大也受到严重影响。当土壤含水率在６％～１０％范围内，６～８月各月份进行的干旱处理与对照（全期湿润）相比，其鲜薯产量差异均达极显著水平。干旱指数为６月＞７月＞８月＞９月。前期干旱比后期干旱对鲜薯产量影响较重。据此，提出了甘薯旱地栽培应充分利用自然降水及水浇地栽培经济用水的技术措施。