Boll size affects the insecticidal protein content in Bacillus thuringiensis (Bt) cotton

Bacillus thuringiensis (Bt) transgenic cotton has been planting in large-scale for more than 10 years in China. It was observed that resistance to bollworm was reduced with the application of big-boll cultivars in China. The objective of the study was to investigate the effects of boll size on the contents of CryIA insecticidal protein in boll shell and cotton seed during the course of boll development. Two experiments were conducted at the Yangzhou University Farm, Yangzhou, China. In 2004, three cultivars including Sikang 1 (small-boll), Xiangza 3 (medium-boll) and Kemian 3 (big-boll) were compared for boll shell volume and 100-seed weight from 10 to 40 days after flowering (DAF), and insecticidal protein contents in boll shell and cotton seed from 10 to 50 DAF. As expected, the differences between cultivars were significant for all the four characteristics. Cultivars with bigger boll shell volume had higher 100-seed weight but lower insecticidal protein contents in both of the boll shell and cotton seed. The correlation between boll size and boll insecticidal protein content was negative (−0.653). The correlation between 100-seed weight and cotton seed insecticidal protein content was significantly negative (−0.645). In 2005, leaf cut (LC) and square removal (SR) treatments were applied to Sikang 1 and Sikang 3. The boll shell volume and 100-seed weight were decreased by LR, but increased by SR. LC significantly enhanced and SR significantly reduced the insecticidal protein contents of boll shell and cotton seed. The correlation between boll size and boll insecticidal protein content (−0.870) and the correlation between 100-seed weight and cotton seed insecticidal protein content were both highly significant and negative (−0.841). Therefore, the results of the study indicated that the boll insecticidal protein content was significantly affected by boll size. The implications of the observed results in breeding, cultural practices and pest management were discussed.     

干旱胁迫下小麦颖果内源激素的变化及其与胚乳发育的关系

为探明干旱胁迫下小麦颖果内源激素与胚乳发育的关系,以小麦品种扬麦16为材料,在幼苗返青至颖果成熟阶段进行干旱处理,采用树脂切片及显微摄影等技术观察小麦颖果和胚乳细胞发育的形态结构特征,并通过酶联免疫吸附法测定颖果生长素(IAA)、脱落酸(ABA)、赤霉素(GA_3、GA_4)、玉米素核苷(ZR)、二氢玉米素核苷(DHZR)的含量。结果显示,干旱胁迫缩短了小麦颖果发育进程,促进颖果早衰,导致颖果发育不良;显著降低了籽粒千粒重、可溶性糖含量和总淀粉含量,提高了蛋白质含量;促进颖果发育早期胚乳细胞分裂和淀粉积累,抑制了发育后期胚乳细胞的分裂、体积扩大和淀粉体充实,并提高了颖果整个发育过程中胚乳蛋白体的积累;提高了颖果发育前期IAA、GA_3、GA_4、ZR和DHZR的含量,ABA含量在整个发育时期均较高。说明干旱胁迫能通过影响颖果内源激素的积累来调控胚乳发育。     

分蘖期不同基因型宿根甘蔗内源激素的测定

对9个甘蔗品种叶片进行生长素、赤霉素、细胞分裂素、脱落酸4种内源激素免疫测定。结果表明:不同的基因型具有不同的激素含量,品种间差异较大。其中,台糖134生长素含量最高,云蔗89/151的赤霉素和细胞分裂素含量最高,Co331的脱落酸含量最高;粤糖93159的生长素和脱落酸含量最低,桂11的赤霉素含量最低,云蔗71/388的细胞分裂素含量最低。     

Hormonal changes in grains of cv. Triumph and its mutant TL43 as affected by nitrogen fertilizer at heading time

A pot experiment was conducted to study the hormonal changes during the grain filling stage in barley lines of Triumph and its mutant TL43 with or without nitrogen fertilizer at heading time. The ABA, ZR and IAA contents in grains were higher under nitrogen treatment (HN) for both genotypes at 30 days post anthesis (DPA). No genotypic differences were observed in GA₃, ABA and IAA content over the grain filling stage and ZR content on 10 DPA exhibited the major difference, which might be associated with the decrease of A-type starch granules in endosperm of TL43. Triumph also showed significantly higher grain weight, lower hordein and glutelin contents than TL43. The changes of these characters might be correlated with the ZR deficiency of TL43 at early grain filling stage.     

不同外源激素对香草兰花芽分化的影响

为探究香草兰花芽分化调控措施及相关机理,在花芽分化前期,以分别喷施细胞分裂素(6-BA)、脱落酸(ABA)、生长素(IAA)和赤霉素(GA)为处理,以清水为对照,分析各处理条件下功能叶内源激素和营养物质含量变化,并统计各处理对花芽分化率的影响。结果表明：6-BA和ABA处理均能增加功能叶中玉米素核苷(ZR)和ABA含量,提高其在花芽分化过程中的蛋白质、可溶性糖和淀粉含量;IAA处理能提高花芽分化中后期功能叶IAA、ABA、ZR和 GA含量,却降低整个分化过程中蛋白质、可溶性糖和淀粉的含量;GA处理降低了ZR和ABA含量,对蛋白质和淀粉含量影响不大;除GA处理外,6-BA、ABA、IAA处理均在一定程度上提高了花芽分化率,以6-BA最为显著,可参考在生产上施用。     

Effect of Growth Regulators and Ethanol on Termination of Dormancy in Potato Tubers

The main objective of this study was to find the best practice of inducing the sprouting of dormant potato tubers. We compared two protocols of breakage of dormancy, which are based on dipping excised potato eyes in an aqueous solution of gibberellic acid (GA₃) and kinetin (standard 1) or in the aqueous solution of GA₃, thiourea, and daminozide (standard 2), with a newly reported approach based on ethanol. We tested the effect of ethanol alone or in combination with GA₃ and/or kinetin on dormancy release and sprouting of the potato tubers. As a model, we used two potato genotypes (cultivars Pasat and Dorota), with long dormancy of 5 and 10 weeks respectively. We showed that the standard 2 was the most effective treatment both for dormancy breaking and in promoting sprout growth, especially for cv. Dorota, for which the treatment induced 82.3% of tuber eye-plugs to sprout 28 days after treatment and to produce 93.2% of emerged plants after subsequent 28 days of cultivation in the greenhouse. For this cultivar, similar efficacy was observed for the combination of 4% ethanol with GA₃ and kinetin. The same concentration of ethanol combined with GA₃ but without kinetin was the most efficient treatment for breaking dormancy of cultivar Pasat. However, the difference between the various treatment combinations was statistically insignificant. Ethanol alone or in combination with kinetin poorly induced breakage of dormancy, confirming the main role of GA₃ in artificial dormancy breaking. Thus our study showed that the standard 2 is the most effective approach for breakage of dormancy at least with long term-dormancy cultivars.     

Effects of the Combined Application of Ethephon and Gibberellin on Growth of Rice (Oryza sativa L.) Seedlings

Abstract

Improvement of early seedling growth, such as seedling emergence and vigor is one of the most important agronomic traits in direct seeding rice cultivation. The effects of two plant growth regulators (PGRs), gibberellic acid (GA₃) and ethephon (ET), on seedling growth under flooded soil conditions at different temperatures and water depths were investigated. The PGRs were applied during the seed soaking process. A single treatment with GA₃ or ET increased seedling growth. However, combined application of GA₃ and ET was more effective than that of GA₃ or ET alone in many cases at both growing temperatures (15 and 20ºC). The growth of different organs in the rice seedlings, such as the coleoptiles, first leaves, and second leaves was also increased by PGR treatment. The nitrogen concentration of the shoot and the ratio of shoot dry weight to shoot length did not differ significantly among the treatments. The results of our study show that rice seedling growth in direct seeding cultivation may be improved by treatment with GA₃ and ET in combination.     

Retardation of shoot growth and promotion of tuber growth of potato plants by paclobutrazol

The relationship between shoot growth and tuber yield in potato plants (Solanum tuberosum L. cv. Russet Burbank) was studied under greenhouse conditions using paclobutrazol [(2R,3R + 2S,3S)-1-(4-chlorophenyl)-4,4-dimethyl-2-(l,2-4-triazol-l-yl)-pentan-3-ol), PP333], a growth retardant. Concurrent with reduction of stem elongation by the application of paclobutrazol to base of the main stem was a decrease in the dry weight of the shoot and an increase in the dry weight of the tuber. The inhibitory effect of paclobutrazol on stem elongation was reversed by gibberellic acid A₃ (GA₃). Leaf content of raffinose sugar and chlorophyll increased upon paclobutrazol treatment.     

Responses of the First Internodes of Hong Mang Mai Wheat to Ethylene,Gibberellins and Potassium

Abstract

Seedlings of Hong Mang Mai wheat ( Triticum aestivum L.) emerge from much deeper in the soil than do other cultivars by elongating their first internode. We examined the roles of ethylene, gibberellins (GA) and potassium in the elongation of the first internode in wheat cultivars. Although ethylene stimulated the elongation of the first internode of Hong Mang Mai in the dark, the ethylene evolution and the expression level of ethylene-receptor-like gene of this cultivar were not greater than those of other cultivars.

In Hong Mang Mai, gibberellin A₃ (GA₃) substantially stimulated the elongation of the first internode in the dark. Maximum elongation of the first internode was obtained by GA₃ at the concentrations of 2.89 × 10^–6 to 2.89 × 10^–7 M. This cultivar responded markedly to gibberellins A₁ and A₃ by elongating the first internode in the dark. A mixture of gibberellins A₄ and A₇ (GA₄₊₇) was not effective in inducing the elongation. Haruhikari, a cultivar having no GA -insensitive-reducing-height (Rht) genes, substantially responded to GA₃, but other cultivars did not. The differences in the sensitivity to GA could account, at least in part, for the varietal differences in the elongation of the first internode in wheat. Takune-komugi, a cultivar whose first internode elongates in response to ethylene, did not respond to GA₃. Thus, there are different mechanisms for the GA- and ethylene-stimulated elongation of the first internode in wheat.

Also, it was suggested that potassium uptake from the soil might function together with endogenous GA in inducing the elongation of the first internode in Hong Mang Mai wheat.     

高效液相色谱法测定玉米内源激素方法的改进研究

以玉米植株为材料,对提取、纯化和利用高效液相色谱法分析测定玉米植株中内源激素生长素(IAA)、脱落酸(ABA)、赤霉素(GA3)和玉米素(ZT)的含量的方法进行改进。针对玉米植株的糖分、叶绿素含量高等特点,对以往的HPLC分析植物内源激素的植物材料前处理方法进行改进。试材用液氮研磨以80%预冷的甲醇浸提,浸提液利用旋转蒸发仪浓缩、石油醚去除色素、乙酸乙酯提取激素、PVP 去除酚类杂质,最后用0.45 um微孔滤膜抽滤,紫外检测器在254 nm波长下检测吸收波长,以甲醇和水位流动相,利用高效液相色谱法检测内源激素含量,回收率分别为IAA 93.79%±7.43%,ABA 95.79%±6.14%,GA388.63%±6.31%,ZT 89.69%±7.34%。     

开花期叶面喷施赤霉素对小黑麦旗叶光合及产量的影响

为给赤霉素在小黑麦生产中的合理使用提供依据,选用小黑麦东农8809和东农95-6654为材料,研究了开花期叶面喷施赤霉素对小黑麦旗叶叶绿素含量、荧光特性及产量的影响。结果表明,叶面喷施赤霉素后,小黑麦叶绿素a、叶绿素b及叶绿素（a＋b）含量提高;叶绿素荧光动力增强,旗叶电子传递活性（Fm）、PSⅡ原初转换效率（Fm/Fv）、光化学淬灭（qP）提高,非光化学淬灭（qN）减少,光合功能增强,千粒重及产量显著提高。其中开花期喷施赤霉素浓度为20mg.L-1时增产作用最好。     

Effects of combinational treatment with ethephon and gibberellic acid on rice seedling growth and carbohydrate mobilization in seeds under flooded conditions

ABSTRACT

Early seedling growth, including seedling emergence and vigor, is crucial in direct seeded rice. In this study, we examined the effects of gibberellic acid (GA₃) and ethephon (ET) on the early growth of direct seeded rice, and on α-amylase activity and soluble sugar content in the seeds. Rice seeds were treated with water (control), ET, GA₃, or ET+ GA₃ and were allowed to grow for 21 days. The results showed that ET and GA₃ synergistically improved the lengths of mesocotyl, coleoptile, mesocotyl+ coleoptile, and first leaf. Moderate synergistic effects of ET and GA₃ were detected in the second and third leaves. ET+ GA₃ treatment induced higher α-amylase activities during early post-germination growth, which is consistent with the longer coleoptile, mesocotyl, mesocotyl+ coleoptile, and first leaf. In addition, ET+ GA₃ induced higher α-amylase activity in the seeds, and consequently, higher sucrose and glucose concentrations than other treatments. These results partially explain the regulatory mechanism underlying the synergistic interaction of ET and GA₃ on rice seedling growth in terms of starch and sugar metabolism in the seeds, and this knowledge is expected to facilitate the practical use of ET and GA₃ in direct seeded rice systems.     

玉米光温敏无雄穗系植株多种植物激素含量的动态变化

以玉米光温敏无雄穗系I17及其正常系N17植株为试验材料,在春季和秋季种植条件下分别测定叶片与雄穗中生长素(IAA)、脱落酸(ABA)、赤霉素(GA3)和玉米素(ZT)的含量,研究植物激素对玉米光温敏无雄穗系植株雄穗发生及其育性的影响。结果表明,春季种植的无雄穗系I17与正常系N17的叶片和雄穗中IAA、GA3、ZT和ABA含量没有明显差异;秋季种植的无雄穗系I17叶片中IAA、GA3和ZT含量在苗期、抽雄期及花粒期均显著低于正常系N17,ABA含量显著高于N17。在植物激素平衡方面,秋季种植的无雄穗系I17叶片中IAA/ABA、GA3/ABA及ZT/ABA的比值均显著低于正常系N17的相应值。IAA、GA3和ZT的严重亏损与ABA的过量积累是引起玉米无雄穗的重要原因之一。     

Influencing seed tuber yield of Ranger Russet and Shepody potatoes with gibberellic acid

Freshly-cut seed pieces of the potato cultivars Ranger Russet and Shepody were dipped in 0, 0.5, 1 or 2 mg/1 Gibberellic Acid (GA₃) prior to planting. GA₃ treatments increased stem and tuber numbers per hill of both cultivars and shifted tuber size profile toward the production of more seed-sized (up to 226 g) tubers and fewer large (greater than 340 g) tubers. The effect of GA₃ on reducing average tuber size was similar for the two cultivars. Total tuber yields were not affected. A 2 mg GA₃/1 seed piece dip decreased the yield of US#1 tubers in Ranger Russet primarily due to a significant increase in yield of tubers less than 226 g. Also, yields of culls were greater after a 1 mg GA₃/1 seed piece treatment, suggesting Ranger Russet is sensitive to this concentration of GA₃. One and 2 mg GA₃/1 seed piece dips to Shepody increased yields of tubers less than 113 g by 93% and reduced the yield of tubers greater than 340 g by 25% to 50%. GA₃ at 1 to 2 mg/1 may be useful in the production of seed potatoes with the cultivar Shepody which tends to produce many large tubers.     

Ground cover, photosynthetic rate and tuber yield of potato (Solanum tuberosum L.) crops from seed tubers with different physiological age modified by foliar applications of plant growth regulators

Summary The modifying effects of applying the plant growth regulators (PGRs) benzylaminopurine (BAP), gibberellic acid (GA₃) and BAP+GA₃ on physiological age were studied. Two experiments with two cultivars, differing in rate of physiological ageing (medium-early Pampeana, medium-late Huinkul) and two storage systems were performed during 1988/89 and 1989/90 in two different potato areas of Argentina. In both seasons seed tubers stored in heaps reached an advanced physiological age at planting, compared with tubers from the cold store. Seed tubers of cv. Pampeana were older than those of Huinkul. compared with control crops, those sprayed with BAP maintained ground cover and photosynthesis for longer, and those sprayed with GA₃ for a shorter period. Consequently tuber yield was decreased by GA₃ in 1988/89, but in 1989/90 all crops treated with PGRs outyielded the control. BAP could overcome effects of advanced physiological age on crop senescence and tuber yield. CIC BA This work was carried out with a research grant from CAFPTA (249/89).     

Growth regulators,photoperiod, and flowering in potatoes

The effect of 25 ppm gibberellic acid (GA₃), 7,500 ppm Gapol^(R) (0.4% molybdate; 0.42% cobalt; 0.56% tungstate; 2.84% borax; 4 ppm indoleacetic acid; 4 ppm naphthyltalamic acid; and 2 ppm ethylenediaminetetraacetic acid) and of two photoperiods (12 and 18 h daily) on flowering of potato cv Marijke was studied under greenhouse conditions. GA³ specifically reduced the number of days required for flowering, and Gapol^(R), or long days, favored bud retention. When combined, only a slight additive effect was observed. In most cases spraying the products on plants subjected to long days resulted in an increase in the number of floral buds, but their attachment to the plant was mainly influenced by the presence of Gapol^(R).     

夜间补光对小麦叶片激素含量及光合特性的影响

为探究夜间补光对小麦生育后期的调控作用,以冬小麦品种豫农186为材料,以自然光照时间为对照,在小麦抽穗后设置夜间人工补光2h、4h和6h三个处理,研究补光时间对小麦叶片内源激素含量、光合特性及产量的影响。结果表明,夜间补光可增加小麦叶面积及旗叶叶绿素含量和光合速率,以补光6h的效果最显著。与自然对照相比,夜间补光显著增加旗叶GA3、IAA、ZR含量,且激素含量的升高幅度随补光时间的延长而增加,但ABA含量受影响较小。夜间补光能显著提高灌浆前期和中期籽粒灌浆速率及千粒重和产量,其中补光6h处理的最大灌浆速率比自然对照增大16.21%,产量提高14.07%。说明小麦抽穗后适当延长光照时间有利于叶片的生长发育,可提高激素含量和光合效率,促进籽粒灌浆,增加产量。     

氮肥后移对春玉米子粒灌浆特性及内源激素的影响

以陕科9号为材料,2019～2020年在陕西榆林灌溉区进行大田试验,在总施氮量相同、基肥和大喇叭口期追肥分别占总施氮量20%和40%条件下,设置4个施氮处理,传统施氮(拔节肥40%,N1)、氮肥后移10%(拔节肥30%+花粒肥10%,N2)、氮肥后移20%(拔节肥20%+花粒肥20%,N3)和氮肥后移30%(拔节肥10%+花粒肥30%,N4),分析各处理子粒灌浆特性、内源激素含量和产量构成。结果表明,氮肥后移各处理2年玉米产量均显著高于传统施肥,N3处理产量最高。氮肥后移增加子粒灌浆速率最大时生长量(W_max)、最大灌浆速率(G_max),延长子粒灌浆活跃期;氮肥后移过量(N4),子粒灌浆参数受到不良影响。同时,N3处理子粒生长素(IAA)含量达到峰值时均较N1处理显著增加51.7%,玉米素(ZR)含量显著增加16.7%,赤霉素(GA₃)含量显著增加28.9%,脱落酸(ABA)含量显著降低18.2%。在陕西灌溉春玉米区,总施氮量270 kg/hm²时,拔节期追肥54 kg/hm²、大喇叭口期追肥108 kg/hm²、花后7 d追肥54kg/hm²为该区玉米高产的优化施氮制度。     

超级稻花后强、弱势粒淀粉合成相关酶活性和激素含量变化及其与籽粒灌浆的关系

 种植4个超级稻品种\[两优培九和Ⅱ优084（杂交籼稻）、淮稻9号和武粳15（粳稻）\]和2个高产对照品种\[汕优63（杂交籼稻）和扬辐粳8号（粳稻）\],观察其结实期强、弱势粒中蔗糖合酶（SuSase）、腺苷二磷酸葡萄糖焦磷酸化酶（AGPase）、淀粉合酶（StSase）和淀粉分支酶（SBE）活性及玉米素+玉米素核苷（Z+ZR）、3 吲哚乙酸（IAA）和脱落酸（ABA）含量的变化,并测定了强、弱势粒灌浆速率。结果表明,超级稻品种强势粒的最大灌浆速率、到达最大灌浆速率的时间、平均灌浆速率和糙米重与对照品种差异较小,超级稻品种弱势粒的灌浆速率和糙米重显著低于对照。灌浆期强、弱势粒的SuSase、AGPase 、StSase 和SBE活性变化及Z+ZR、IAA 和ABA 含量变化均呈单峰曲线。弱势粒的SuSase、AGPase、StSase 和SBE的峰值活性和平均活性及其Z+ZR 和IAA的峰值含量和平均含量均低于强势粒。弱势粒的ABA 峰值含量和平均含量显著高于强势粒,超级稻品种高于对照品种。籽粒灌浆速率与SuSase、AGPase和StSase 活性及Z+ZR 和IAA含量均呈显著或极显著正相关,与SBE活性及ABA含量的相关不显著。说明超级稻品种弱势粒中较低的SuSase、AGPase和StSase活性及较低的Z+ZR和IAA含量是其灌浆速率小、粒重轻的一个重要原因。     

OsSUV3 transgenic rice maintains higher endogenous levels of plant hormones that mitigates adverse effects of salinity and sustains crop productivity

Background

The SUV3 (suppressor of Var 3) gene encodes a DNA and RNA helicase, which is localized in the mitochondria. Plant SUV3 has not yet been characterized in detail. However, the Arabidopsis ortholog of SUV3 (AT4G14790) has been shown to be involved in embryo sac development. Previously, we have reported that rice SUV3 functions as DNA and RNA helicase and provides salinity stress tolerance by maintaining photosynthesis and antioxidant machinery. Here, we report further analysis of the transgenic OsSUV3 rice plants under salt stress.

Findings

The transgenic OsSUV3 overexpressing rice T₁ lines showed significantly higher endogenous content of plant hormones viz., gibberellic acid (GA₃), zeatin (Z) and indole-3-acetic acid (IAA) in leaf, stem and root as compared to wild-type (WT), vector control (VC) and antisense (AS) plants under salt (200 mM NaCl) stress condition. A similar trend of endogenous plant hormones profile was also reflected in the T₂ generation of OsSUV3 transgenic rice under defined parameters and stress condition.

Conclusions

In response to stress, OsSUV3 rice plants maintained plant hormone levels that regulate the expression of several stress-induced genes and reduce adverse effects of salt on plant growth and development and therefore sustains crop productivity.