AbstractCanola (Brassica napus L.), is the most important oilseed crop due to high oil contents and low concentration of erucic acid and glucosinolates. In Pakistan, oil seed production is not sufficient to fulfill the needs of the country. Thus, the planned experiment was aimed to evaluate the performance of different canola cultivars i.e. Faisal Canola, Pakola, PARC Canola hybrid and Rainbow at grown under various soil applied boron (B) levels viz., 0, 1, 2?kg ha?1 under a rainfed environment. The experiment was laid out in randomized complete block design with four replications. Among the canola cultivars, the maximum seed oil contents were recorded in cultivar ‘Pakola’ whereas, higher linolenic acid and protein were recorded in cultivar ‘Faisal canola’ as compared to other cultivars. A synergistic effect was found between various levels of B and quality parameters of the canola seed; as higher concentration of oil contents were found when B was applied 2?kg ha?1. Conversely the linolenic acid showed the antagonistic behavior with the various B levels. On the other hand, protein contents, oleic acid and erucic acid revealed non-significant differences under different B application rates. In conclusion, the cultivar ‘Pakola’ provided the highest oil content when the B was applied at 2?kg ha?1; the low concentration of unsaturated fatty acid was observed in ‘PARC canola’ cultivar in the Pothwar region of Punjab, Pakistan. 相似文献
Limited water availability is a severe threat to the sustainability of crop production. Exogenous application of glycinebetaine (GB) has been found very effective in reducing the adverse affects of water scarcity. This study was conducted to examine the role of exogenous GB application in improving the yield of hybrid sunflower (Helianthus annuus L.) under different irrigation regimes. There were three levels of irrigation: Control (four irrigations), three irrigations (irrigation missing at budding stage) and two irrigations (irrigation missing at budding and grain formation stage) in the experiment. While GB was applied exogenously at 100 mM GB each at budding and grain formation stages, the Control treatment did not receive any GB application. Data regarding yield, yield components and quality parameters showed that water stress reduced the head diameter, number of achene per head, 1000-achene weight and yield. Nonetheless, it was significantly improved by the exogenous GB application. Among the qualitative characteristics, protein contents were significantly increased by water stress at different growth stages but were reduced by exogenous GB application. Whilst oil contents were reduced by drought at different stages, GB application, however, did not ameliorate the negative effect of drought stress on achene oil contents. The effects of water stress and foliar application of GB were more pronounced when applied at vegetative stage than at the reproductive stage. Moreover, exogenous GB application was only advantageous under stress conditions. 相似文献
For examining the probability of increase in the occupation ratio of inoculated rhizobium in nodules, various Rj-soybean cultivars including the Rj2Rj3Rj4-lines of soybean were grown in a field of the Kyushu University Farm. Bradyrhizobium japonicum USDA110 that carries uptake hydrogenase (Hup+) was used as an inoculum. The relative efficiency of nitrogen fixation generally increased by the inoculation. However, there were no significant differences in the effects among the genotypes of the host plants. The occupation ratio of serogroup USDA110 in the nodules on the taproot of the inoculated plants was in the range of 77–100%, suggesting that the B. japonicum strain USDA110 infected taproots immediately after inoculation. The occupation ratios in the nodules on the lateral roots were 53–67, 40–86, 63–83, and 62–77% in inoculated plants of the non-Rj-, Rj2Rj3-, Rj4-, and Rj2Rj3Rj4-genotypes, respectively, and they decreased in all the genotypes with the progression of growth. At the time of the first sampling, the occupation ratios on the lateral roots of these Rj2Rj3Rj4-genotypes showed values intermediate between those of IAC-2 (Rj2Rj3) and Hill (Rj4) , which were the parent cultivars of the Rj2Rj3Rj4-lines, B340, B349, and C242. The reduction in the occupation ratio of the serogroup USDA110 for about 1 month after the first sampling was the lowest (0.13–0.16) in the Rj2Rj3Rj4-genotypes, excluding B349, followed by the non-Rj- and Rj2Rj3-genotypes and highest (0.52–0.69) in the Rj4-genotypes, excluding Hill. Therefore, it was considered that the population of compatible rhizobia with host soybean plants increased in the rhizosphere with the progression of the development and growth. The results showed that with the expansion of the root area of host plants, the occupation ratio of type A rhizobia including the serogroup USDA110 was high. Therefore, the Rj2Rj3Rj4-genotypes were superior to other Rj-genotypes in terms of the inoculation effects of nodulation type A rhizobium, B. japonicum USDA110. However, the preference of the Rj2Rj3Rj4-genotype for serogroup USDA110 is not sufficient to rule out the competition with the other serogroups in this study. Therefore, the study should be centered on the isolation of more efficient (Hup+) and highly compatible rhizobial strains with the Rj2Rj3Rj4- genotypes. 相似文献
ABSTRACT This study reports the relationship of the leaf ionic composition with the grain yield and yield components of wheat in response to salinity x sodicity and salinity alone. The study was conducted in soil culture in pots with three treatments including control (ECe 2.6 dS m? 1 and SAR 4.53), salinity (ECe 15 dS m? 1 and SAR 9.56), and salinity x sodicity (ECe 15 dS m? 1 and SAR 35). The soil was treated before being put in the pots and the pots were arranged in a completely randomized factorial arrangement with five replications. The seeds of three wheat genotypes were sown directly in the pots and the study was continued till the crop maturity. At booting stage, the leaf second to the flag leaf of each plant was collected and analyzed for sodium (Na+), potassium (K+), and chloride (Cl?). At maturity, plants were harvested and data regarding grain yield and yield components were recorded. This study shows that salinity and sodicity in combination decreases the grain yield of wheat more than the salinity alone with a greater difference in the sensitive genotype. This study also shows that as for salinity, the maintenance of lower Na+ and higher K+ concentrations and higher K+: Na+ ratio in the leaves relates positively with the better development of different yield components and higher grain yield in saline sodic soil conditions. Although, the leaf Cl? concentration was increased significantly by salinity as well as salinity x sodicity and would have affected the growth and yield, yet it does not seem to determine the genotypic tolerance or sensitivity to either salinity or salinity x sodicity. 相似文献
The zinc (Zn) requirement of a maize (Zea mays L.) hybrid (‘FHY-396’) and an indigenous variety (‘EV-7004’) was measured at low (22.4 ± 5°C) and high (28.8 ± 5°C) root-zone temperatures (RZT). Four Zn rates (0, 3, 9 and 27 mg kg?1 soil) were applied to a calcareous loam soil in pots for the glasshouse study. Shoot and root dry matter yields were significantly more at the higher RZT. Regardless the RZT, maximum relative shoot dry matter yield in hybrid and variety was produced, respectively, at 9 and 3 mg Zn kg?1 soil. Zinc concentration in roots and shoots of both the cultivars increased with Zn rates and it was significantly more at the higher RZT. Cultivars differed in critical Zn concentration (CZnC) required for maximum shoot dry matter yield. The CZnC ranged from 25 to 39 μg Zn g?1 plant tissue for optimum growth of both the cultivars at low and high RZT. 相似文献
Wheat (Tritcum aestivum L.) genotypes were screened and characterized for performance under salt stress and/or water‐logging. In a solution‐culture study, ten wheat genotypes were tested under control, 200 mM–NaCl salt stress and 4‐week water‐logging (nonaerated solution stagnated with 0.1% agar), alone or in combination. Shoot and root growth of the wheat genotypes was reduced by salinity and salinity × water‐logging, which was associated with increased leaf Na+ and Cl– concentrations as well as decreased leaf K+ concentration and K+ : Na+ ratio. The genotypes differed significantly for their growth and leaf ionic composition. The genotypes Aqaab and MH‐97 were selected as salinity×water‐logging‐resistant and sensitive wheat genotypes, respectively, on the basis of their shoot fresh weights in the salinity × water‐logging treatment relative to control. In a soil experiment, the effect of water‐logging was tested for these two genotypes under nonsaline (EC = 2.6 dS m–1) and saline (EC = 15 dS m–1) soil conditions. The water‐logging was imposed for a period of 21 d at various growth stages, i.e., tillering, stem elongation, booting, and grain filling alone or in combinations. The maximum reduction in grain yield was observed after water‐logging at stem‐elongation + grain‐filling stages followed by water‐logging at grain‐filling stage, booting stage, and stem‐elongation stage, respectively. Salinity intensified the effect of water‐logging at all the growth stages. It is concluded that the existing genetic variation in wheat for salinity × water‐logging resistance can be successfully explored using relative shoot fresh weight as a selection criterion in nonaerated 0.1% agar–containing nutrient solution and that irrigation in the field should be scheduled to avoid temporary water‐logging at the sensitive stages of wheat growth. 相似文献
Field experiments were conducted on wheat during 2017–2018 and 2018–2019 under rainfed conditions. The statistical significance between treatment means was determined at 5% significance level. Data were recorded on weed density, protein, fat and ash contents of wheat grains. Weed density in shallow tillage was highest (20.67?m?2) while it was lowest (14.23?m?2) in deep tillage. In weed control factor, weed density was highest in weedy check (33.10?m?2), followed by parthenium aqueous extract (21.50?m?2), and lowest (6.79?m?2) in plots treated with Affinity (isoproturon?+?carfentrazone). Results showed that the highest crude protein content (10.88%) was recorded in deep tillage, while lowest (10.45%) in shallow tillage, indicating that tillage depths have an impact on wheat grains protein content. For weed control factor, the crude protein content was highest (11.98%) in Affinity treated plots, followed by herbicides, Buctril super (bromoxynil?+?MCPA) (11.44%) and Puma super (fenoxaprop-p-ethyl) (11.12%). Hence, the control measures also affected crude protein content of wheat grains, which is also obvious from the weedy check where wheat grains crude protein content was lowest (9.73%). The two years combined data analysis also showed the highest crude fat content (1.75%) in deep tillage treatments followed by normal tillage (1.67%) and lowest fat content (1.53%) in shallow tillage. For ash content, the highest content (3.03%) was with Affinity herbicide treatments, followed by Buctril super (2.74%) and Puma super (2.48%) herbicides. In conclusion, both the tillage and herbicides indicated positive effects on the nutritive status of wheat grains.
Salinity is a crucial problem which has affected crop productivity globally. Ascorbic acid is considered helpful against abiotic stresses due to its powerful antioxidant potential. In the pot experiment, salinity stress (0, 35, 70, and 105?mM) was applied to sweet peppers in split doses after 20 days of transplantation. To mitigate the adverse effects of salinity, ascorbic acid (0, 0.40, 0.80, and 1.20?mM) was applied as foliar spray after a 6-day interval during vegetative growth. Sweet pepper plants sprayed with distilled water (control) recorded maximum plant height (cm), leaf area (cm2), number of branches, stem diameter (mm), number of fruit plant?1, fruit diameter (cm), yield plant?1 (g), and chlorophyll content (mg 100?g?1), while the maximum polyphenol oxidase (PPO) activity (unit mg protein?1 min?1) and ascorbate peroxidase (APX) activity (unit mg protein?1 min?1) were recorded in plants treated with 70?mM NaCl application. Salinity stress beyond 70?mM significantly reduced all the studied parameters. An ascorbic acid concentration of 1.20?mM significantly mitigated the negative effects of salt stress and recorded maximum plant height (cm), number of leaves plant?1, leaf area (cm2), number of branches plant?1, stem diameter (mm), number of fruit plant?1, fruit diameter (cm), yield plant?1 (g), chlorophyll content (mg 100?g?1), PPO activity (unit mg protein?1 min?1), and APX activity (unit mg protein?1 min?1). Hence, a 1.20?mM concentration of foliar ascorbic acid could be used in saline conditions up to 70?mM of sodium chloride (NaCl) for better growth, productivity, and enzymatic activity of sweet peppers.
Wheat (Triticum aestivum L.) is a staple food in many countries and is regarded as a vital source of nutrition. Drought is one the most prevalent limitations to wheat growth and development. Herein a two year study was conducted using 25 diverse wheat genotypes obtained from the gene pool of various research institutes of Pakistan to characterize their drought tolerance using various physiological indices like relative water content (RWC), relative dry weight (RDW), water saturation deficit (WSD), relative water loss (RWL), flag leaf area (LA), chlorophyll content index (CC) and their association with the grain yield (GY). Analysis of variance (ANOVA) indicated the presence of significant amount of differences and genetic diversity among genotypes under study. Correlation analysis exposed positive association of CC and LA with GY. However, RWC was shown to have a highly significant and negative association with WSD and RWL. Principal component analysis (PCA) showed that out of the 7 PCs only 2 were significant having eigenvalues >?1; cumulatively accounting for 88.70% and 73.03% of the total variation under control and drought stress conditions, respectively. Strikingly the results of the PCA biplots and cluster heat map exposed G1 (Barani-17), G2 (Dharabi-11), G3 (Ehsan-16), G4 (Chakwal-50), G17 (Ujala-2016) and G23 (Kohistan-97) as potential drought tolerant genotypes. Selection of the positively associated indices would be fruitful and the tolerant genotypes having drought tolerance potential could be utilized in future wheat breeding programs to develop high yielding and drought tolerant genotypes.
