干旱胁迫对不同基因型烤烟品种旺长期光合作用的影响

通过控水盆栽试验手段,在烤烟旺长期研究比较新品种云201、云202、云203和K326在不同程度干旱下部分光合生理指标的变化趋势,初步了解四个不同基因型烤烟品种对干旱胁迫的适应性能力的大小。试验结果表明,通过对各项光合生理指标综合分析可知不同基因型烤烟品种对干旱胁迫的敏感程度和忍耐力存在明显差异,云202对干旱胁迫的生理反映最为迟钝,K326对干旱胁迫反映最为敏感,云201与云203介于两者之间且云203对干旱胁迫的生理指标变化幅度高于云201。从光合生理水平了解不同基因型烤烟品种的内在特性,可为不同品种适应不同的栽培环境提供理论依据并建立合理的栽培制度,同时为不同基因型烤烟品种的抗逆育种提供理论指导。     

抗旱剂拌种处理对小麦萌发和幼苗生长的影响

干旱胁迫下用抗旱剂Ⅰ号拌种处理小麦种子可以提高小麦出苗率，促进根系发育，增加根冠比。处理后，幼苗的生理生化指标均高于对照，可使幼勒在较低水势下保持正常生长。     

Seed treatments to overcome salt and drought stress during germination in sunflower (Helianthus annuus L.)

The treated seeds (control, KNO₃ and hydropriming) of sunflower (Helianthus annuus L.) cultivar Sanbro were evaluated at germination and seedling growth for tolerance to salt (NaCl) and drought conditions induced by PEG-6000 at the same water potentials of 0.0, −0.3, −0.6, −0.9 and −1.2 MPa. Electrical conductivity (EC) values of the NaCl solutions were 0.0, 6.5, 12.7, 18.4 and 23.5 dS m⁻¹, respectively. The objective of the study was to determine factors responsible for germination and early seedling growth due to salt toxicity or osmotic effect and to optimize the best priming treatment for these stress conditions.

Results revealed that germination delayed in both solutions, having variable germination with different priming treatments. Germination, root and shoot length were higher but mean germination time and abnormal germination percentage were lower in NaCl than PEG at the same water potential. Seeds were able to germinate at all concentrations of NaCl but no seed germination was observed at −1.2 MPa of PEG treatments. NaCl had less inhibitor effect on seedling growth than the germination. It was concluded that inhibition of germination at the same water potential of NaCl and PEG resulted from osmotic effect rather than salt toxicity. Hydropriming increased germination and seedling growth under salt and drought stresses.     

Pod photosynthesis and drought adaptation of field grown rape (Brassica napus L.)

In rape (Brassica napus L., cv. Global) seed growth mainly depends on husk CO₂ assimilation. In irrigated plants, the net photosynthetic rate (A_max) was 10–13 μmol CO₂ m⁻² s⁻¹ in non-maturing pods and correlated with nitrogen content. The stomatal conductance of water vapour (g_H2O) was 0.3 mol m⁻² s⁻¹ in non-maturing pods. The photosynthetic nitrogen use efficiency (NUE) was 8.3 μmol CO₂g⁻¹ N s⁻¹, about one-third of that in leaves. The photosynthetic water use efficiency (WUE; A_maxg_H2O⁻¹) was similar in pods and leaves. In severely droughted plants, the photosynthetic rate was reduced to 38%. The seed growth rate, however, was not influenced by intermittent periods of water stress, indicating translocation of assimilates to the seeds. The drought resistant character of the pods was due to low specific area, succulence, low stomatal conductance causing a small decrease of ΔΨ day⁻¹ during soil drying and maintenance of high relative water content during severe drought. A mathematical formulation of the pod water release curve was undertaken. © (1997) Elsevier Science B.V.     

玉米种子萌发期抗旱性鉴定方法及不同杂交种抗旱性比较研究

用PEG-6000高渗溶液模拟土壤水分胁迫的方法,比较了培养介质、浸种时间对不同粒质量类型玉米种子发芽率的影响,并采用砂培不浸种方式,研究了黄淮海地区近几年审定的32个玉米杂交种萌发期的抗旱性。结果表明:不同类型的玉米品种,在纸培模式下20%PEG渗透胁迫处理的发芽率均低于或等于25%,远低于砂培模式。砂培模式下,不浸种处理的发芽率总体好于浸种24 h和48 h处理。砂培不浸种方式下,渗透胁迫处理不同程度地降低了32个玉米杂交种种子的发芽率;大多数品种初生根条数低于对照,胚芽长和胚根长均减小,胚芽长比胚根长减小的程度大,胚芽干质量显著降低。     

Effects of previous cropping on seed yield and yield components of oil-seed rape (Brassica napus L.)

Information about the effect of the preceding crop or crop combination on the seed yield of oil-seed rape is extremely scarce. Experiments were carried out in northwest Germany to investigate the effect of different preceding crops on the growth, seed yield and yield components of oil-seed rape. The two directly preceding crops, wheat and oil-seed rape, had only a negligible and non-significant effect on the seed yield of the following oil-seed rape crop. Oil-seed rape grown after wheat had more pods per plant, due to an increase in the number of pods on the higher category branches. In contrast, the seed yield and yield components were more affected by the cropping sequence, i.e. the crops 2 years before. Averaged over two experimental years, the greatest yields were observed in oil-seed rape following the sequence peas-wheat (694 g m⁻²), whereas the smallest seed yield occurred after 2 years of oil-seed rape cropping (371 g m⁻²). The differences in the seed yield were again associated with more pods per plant, which compensated for the lower number of plants m⁻², whereas the number of seeds per pod and the mean seed weight were almost unaffected by the previous cropping. It was not possible to relate the described differences to the crop development, since differences in the biomass caused by the previous cropping were only significant at maturity. Oil-seed rape grown after 2 years of oil-seed rape had the highest ratings of stem canker (Leptosphaeria maculans) as well as verticillium wilt (Verticillium dahliae). But the general level of the diseases was low, and therefore other causes for the effects described must be considered.     

Effects of water stress applied at different growth stages to Brassica napus L. var. oleifera on yield, yield components and seed quality

In pot experiments under controlled conditions we investigated the effects of water stress on oilseed rape. Yield and yield components were mainly affected by water shortage occurring from flowering to the end of seed set. The greatest reduction (48%) was observed when only 37% of full water requirement was supplied to the plant during this stage. The number of seeds per plant was the main yield component affected. Some compensation occurred when the water supply was restored. The 1000-seed weight was only affected by a water stress from the stage when the pods were swollen until the seeds colored stage. The results demonstrated a marked reduction in oil concentration when water deficit occurred from anthesis to maturity. There was an inverse relationship between oil and protein concentration. The most marked effect observed in this experiment was on the glucosinolate concentration where increases of up to 60% were observed. These results may explain effects on seed quality of field grown oilseed rape.     

Effect of Seed Size on Germination and Seedling Growth in Greengram (Vigna radiata L. Wilczek) and Blackgram (Vigna mungo L. Hepper) Cultivars

The effect of seed size on germination and seedling growth was assessed using cultivars of greengram and blackgram. Significant positive correlation was noticed between seed size and germination, seedling height, root length, primary leaf size and seedling weight. The possible advantages of choosing cultivars with heavier seeds for attaining better crop stand especially under rainfed situation are discussed.     

败脂酸钙拌种+赤酶酸浸种复合处理对干旱胁迫下小麦生长的效应

干旱胁迫下用败脂酸钙拌种 赤酶酸浸种复合处理小麦种子可以提高出苗率,增加根冠比,幼苗的各项生化指标均高于对照.8h浸种 2%拌种处理的出苗效果最好,出苗率为94%,高于正常水分对照.     

外源茉莉酸甲酯对UV-B胁迫下颠茄生物碱积累及TAs代谢途径调控的机制探究

In order to preliminarily explore the mechanism of TAs metabolic pathway in A. belladonna treated with exogenous methyl jasmone under UV-B stress, the effects on the contents of hyoscyamine and scopolamine, the upstream products in alkaloid synthesis, signal molecule and the expression level of key enzyme genes of secondary metabolism were studied under different concentrations of exogenous MeJA and different treatment time under using A. belladonna as materials. UV-B stress treatment significantly reduced the contents of hyoscyamine and scopolamine, inhibited the accumulation of precursors in the TAs synthesis pathway, which harmful to TAs synthesis. The content of TAs in A. belladonna increased to some extent, the contents of precursor amino acids (ornithine, arginine), polyamine content and key enzymes activities in the synthesis of putrescine in the secondary metabolic pathway all increased to some extent after treatment with the appropriate concentration of MeJA. The concentrations of signal molecule NO firstly increased and then decreased with the rising MeJA concentration, and reached the highest when MeJA concentration was 250 μmol L ^-1. The expression of key enzyme genes in TAs synthesis pathway showed that exogenous MeJA could increase the relative gene expression levels of TR I, PPAR, H6H to some extent. Those indicated that exogenous MeJA could induce the increase in the contents of upstream products in TAs synthesis by stimulating the burst of NO resulted in more precursor materials for the TAs synthesis pathway and affect the high expression of TR I, PPAR and H6H. It alleviated the inhibiton of UV-B stress on TAs of A. belladonna and increased the contents of hyoscyamine and scopolamine effectively. The results provided a theoretical basis for further studying the mechanism of exogenous elicitors to regulate the TAs secondary metabolic pathway of A. belladonn under stress, and effectively improved the stress resistance of A. belladonn and the accumulation of medicinal ingredients in actual production.     

外源SLs和纳米K2MoO4对干旱胁迫下油菜种子萌发的影响

干旱胁迫是油菜种子萌发和生长发育的主要限制因子之一。以甘蓝型油菜品种Q2（抗旱型）和秦优8号（干旱敏感型）为试验材料,研究干旱对油菜种子萌发的影响,探讨外源生长调节物质独脚金内酯（SLs）和纳米材料（n-K₂MoO₄）对干旱胁迫下油菜种子萌发的生理调控作用。结果表明,干旱胁迫显著抑制种子萌发,SLs和n-K₂MoO₄均可显著提高发芽率,增加幼苗干重和子叶叶绿素含量,提高超氧化物歧化酶、过氧化物酶活性及可溶性糖、脯氨酸含量,降低丙二醛含量。0.10µmol/L GR24+0.24mmol/L K₂MoO₄对干旱胁迫下种子萌发和氧化损伤的缓解效应较好。外源SLs和n-K₂MoO₄通过提高油菜种子萌发期的保护酶活性和渗透调节物质含量来提高抗旱性。本研究表明植物激素和纳米材料在农业生产中具有应用价值。     

Adaptation and yielding ability of castor plant (Ricinus communis L.) genotypes in a Mediterranean climate

Successful castor (Ricinus communis L.) cropping in Greece depends on the yielding ability and yield stability of the cultivars (hybrids or inbreds) as well as the reliability of production systems. The adaptation and yielding ability of 19 modern castor oil genotypes were studied for 3 years in two sites of Northern Greece. Genotypes combining high seed and oil yield and desirable morphological characteristics were tested for 2 or 3 years, whereas the rest were tested for 1 year only. The growing period in both locations was long enough for ripening the first raceme and a number of secondary racemes depending on the genotypes. The plant height was dependent mainly on the genotypes but also was affected by the site and the year of the experimentation and ranged from 79 to 278 cm. The seed yield varied between 2.5 and 5.0 Mg ha⁻¹, values that are among the highest reported in the literature. The seed yield was higher in the site where plants produced and ripened more secondary racemes. The seed oil content was dependent mainly on the genotype and ranged from 44.5 to 54.2%. The oil yield followed the changes in seed yield. The variation in seed yield between years was low and in most genotypes less than 20%. Results indicate that the castor oil crop was satisfactorily adapted in the area.     

Plant position effect on seed weight,oil content,and oil composition in sesame

Summary Within-plant variation was studied in seed samples of sesame (Sesamum indicum L.). Central and lateral capsules were sampled in three entries. Three capsule postions-basal (nodes 16 to 20), intermediate (nodes 21 to 25), and apical (nodes 26 to 30)-were sampled in four other entries. Nuclear magnetic resonance and gas liquid chromatography were used to characterize within-and among-plants variation in the same genotype for oil content and its fatty acid composition, respectively.Central capsules had heavier seeds, and their oil had more palmitic and oleic acids than had seeds from the two lateral capsules. However, central capsules had seeds with less oil content, and the oil had less stearic, linoleic, and arachidic acids than seeds from lateral capsules. Seed weight and arachidic acid were found to be constant in seeds from capsules located at different nodes along the plant. Oil content had a significant variation with capsule position along the plant in only one entry. Percentages of palmitic and linoleic acids were lower, and those of stearic, oleic, and linolenic acids were higher in seeds from the apical capsules. In almost all cases, capsules located in the intermediate and basal sections had a similar oil composition. However, there was a lack of consistency in the within-plant variation from plant to plant for the different traits studied. It was concluded that within-plant variation need be taken into account only if the experiment was set up to detect small differences between treatments. Among-plants variation was found to be influenced by plant genotype.     

Improvement in hydroxy fatty acid seed oil content and other traits from interspecific hybrids of three Lesquerella species: Lesquerella fendleri , L. pallida, and L. lindheimeri

Interspecific hybridization offers potential to improve the hydroxy fatty acid (HFA) content of lesquerella. Lesquerella fendleri is currently being developed for cultivation as a potential new industrial oilseed crop because of its seed productivity. However, it has lower HFA content compared to L. pallida and L. lindheimeri. The objectives of this research were to improve the HFA oil content of L. fenderi through interspecific hybridization and to characterize hybrids and successive generations for seed oil fatty acid profile, fertility, seed set and other morphological traits. In this work, three species were successfully hybridized, self-pollinated, and backcrossed. Ovule culture was used in some cases to produce progeny where interspecific hybrids did not produce viable embryos. The traits measured were petal length, ovules per silique, seeds per silique, and weight of 1000 seed. Patterns of leaf trichomes were used to distinguish between parents and hybrids. Seed per silique indicated that autofertility occurred in L. pallida but not in the other two species. HFA oil content of L. fendleri seed were 50.5% compared to 80 and 84% for L. pallida and L. lindheimeri, respectively. The HFA oil content of the hybrids ranged from 57 to 70% in A₂ and A₃ generations, and the range of values depended on the parents used in the crosses. These measurements will help predict the value of different interspecific crosses for breeding. Segregation for various yield related traits should allow selection for favorable improvements in the HFA trait and in seed yield.     

Competition, growth and yield of faba bean (Vicia faba L.)

This paper reviews current knowledge regarding the influence of plant density on the growth and yield of the faba bean crop (Vicia faba L.). An analysis is also made of sowing rate and other factors that may modify optimum plant density, including environmental conditions; in this sense, should be made a differentiation between faba crops grown in temperate conditions and those grown in Mediterranean and semi-arid conditions. The genotype also prompts variations in optimum plant density, depending on the botanical type (mayor, equina or minor) and the growth habit (determinate versus indeterminate) of the cultivar selected. Sowing date also influences optimum seeding rate, which is lower for autumn–winter sowing under temperate and Mediterranean conditions and increases as the sowing date is delayed. For the spring-sown crops typical of temperate conditions, optimum plant density will be higher due to the shorter growing season. With a longer growing season and under optimum environmental conditions, there is normally no additional response to densities over 20 plants m⁻², while in suboptimal conditions, optimum plant density may increase to over 60 plants m⁻². Although the faba bean crop displays considerable plasticity in response to variations in plant density, mainly with regard to number of pods per square meter, it is not wholly clear to which component of yield this should really be ascribed. Number of stems per plant appears to be the most influential factor, although further research is required to confirm this.     

Effect of depth of fertilizer banded-placement on growth,nutrient uptake and yield of oilseed rape (Brassica napus L.)

A better understanding of crop growth and nutrient uptake responses to the depth of fertilizer banded-placement in the soil is needed if growth and nutrient uptake responses are to be maximized. A two-year field study covering two rape seasons (2010–2011 and 2011–2012) was conducted to examine the effect of banded-placement of N–P–K fertilizer at various depths on growth, nutrient uptake and yield of oilseed rape (Brassica napus L.). The results showed that fertilization at 10 cm and 15 cm soil depth produced greater taproot length and dry weight than fertilization at 0 cm and 5 cm. 0 cm and 5 cm deep fertilization significantly increased the lateral root distribution at 0–5 cm soil depth, while 10 cm and 15 cm deep fertilization induced more lateral root proliferation at 5–15 cm soil depth. At 36 days after sowing (DAS), 5 cm deep fertilization produced better aboveground growth and nutrient uptake than 10 cm and 15 cm deep fertilization. However, reversed results were observed after 36 DAS. 10 cm and 15 cm deep fertilization produced more rapeseed than 0 cm and 5 cm deep fertilization, moreover, the yield difference was more significant in drought season (2010–2011) than in relatively normal season (2011–2012). In summary, these results preliminarily suggest that both 10 cm and 15 cm are relatively proper fertilizer placement depth when the practice of banding fertilizer is used in oilseed rape production. But from the viewpoint of diminishing the production cost, 10 cm deep fertilization should be recommended in actual farming. Because 15 cm deep fertilization may require higher mechanical power input, and thus resulting in higher cost of production.     

种子抗旱剂对油菜生长发育与产量的影响

利用抗旱剂对油菜种子进行丸粒化处理，田间试验研究结果表明：不同抗旱剂处理对油菜的生长发育、农艺性状及产量形成有不同程度的影响。使用抗旱剂可在一定程度上改善油菜的经济性状和产量结构，提高油菜籽产量，尤其对改善丸粒化油菜种子的发芽率、出苗率和种子活力，增加植株高度以及降低有效分枝点高度均有显著效果，从而为种子抗旱剂的有效利用，实现油菜大面积抗旱保苗提供了一条有效途径。     

Effect of preceding crop combination and N fertilization on yield of six oil-seed rape cultivars (Brassica napus L.)

Information about the effect of the cropping history on the seed yield of oil-seed rape is extremely scarce. In 1992/93 and 1994/95, the effects of different preceding crop combinations (winter barley and winter wheat as preceding crops, oil-seed rape and wheat as pre-preceding crops) on the yield of six double low oil-seed rape cultivars were examined in a field trial at Hohenschulen Experimental Farm, north-west Germany. In addition, eight nitrogen treatments (different amounts and distribution patterns) were tested for their potential to reduce negative effects of the preceding crops. Following the cropping sequence of oil-seed rape then wheat, oil-seed rape yielded only 3.12 t ha⁻¹; after oil-seed rape then barley, the yield was 3.43 t ha⁻¹ compared with 3.77 t ha⁻¹ following wheat then barley and 3.71 t ha⁻¹ following wheat then wheat. The number of seeds per m² showed a similar pattern, whereas the thousand-seed weight partly compensated for the reduced seed number. It was highest if oil-seed rape was grown 2 years previously. The cultivars differed significantly in their yield potential. Express (3.79 t ha⁻¹) yielded 0.6 t ha⁻¹ more than Falcon (3.18 t ha⁻¹). Increasing amounts of fertilizer-N (80–200 kg N ha⁻¹) increased the seed yield from 3.21 t ha⁻¹ to 3.84 t ha⁻¹. Changes in the distribution pattern within one fertilizer amount had no effect on seed yield. In addition, no interactions between preceding crop combination and the different cultivars or N treatments occurred. It is concluded that crop management cannot totally eliminate the negative effects of an unfavourable cropping history on the seed yield of oil-seed rape.     

Effect of different planting times on the quantitative variation of total seed isoflavone content and composition in Korean soybean cultivars (Glycine max (L.) Merr.)

Journal of Crop Science and Biotechnology - There is great interest in the enhancement of isoflavones as one of the functional ingredients in soybean. This study aimed to investigate the effects of...     

Co-location of seed oil content,seed hull content and seed coat color QTL in three different environments in <Emphasis Type="Italic">Brassica napus</Emphasis> L.

Increasing seed oil content is an important breeding goal for Brassica napus L. (B. napus). The identification of quantitative trait loci (QTL) for seed oil content and related traits is important for efficient selection of B. napus cultivars with high seed oil content. To get better knowledge on these traits, a molecular marker linkage map for B. napus was constructed with a recombinant inbred lines (RIL) population. The length of the map was 1,589 cM with 451 markers distributed over 25 linkage groups. QTL for seed oil content, seed hull content and seed coat color in three environments were detected by composite interval mapping (CIM) tests. Eleven QTL accounted for 5.19–13.57% of the variation for seed oil content. Twelve QTL associated with seed hull content were identified with contribution ranging from 5.80 to 22.71% and four QTL for seed coat color accounted for 5.23–15.99% of the variation. It is very interesting to found that co-localization between QTL for the three traits were found on N8. These results indicated the possibility to combine favorable alleles at different QTL to increase seed oil content, as well as to combine information about the relationship between seed oil content and other traits.