No abstract

No abstract

No abstract

No abstract

Under invivo conditions (ambient-air temperature), the relationship between low temperature stress and the response of some different mango cultivars was monitored. Some biochemical events that occur following cold exposure of mango trees leaves were detected to evaluate their ability to acquire cold injury during exposure to low temperature. The cultivars of Alphonso, Baladi, Bullock's Heart, Helmand, Hindi Besennara, Mabrouka, Mestekawy, Nabeeh, Oweisi, Spates, Taimour and Zebda which grown in private orchard in Fayoum Governorate, Egypt were selected to verify this aim. This study was carried out during the period from November to March of during years; 2012 and 2013. The following results were stated: the detected leaf compositional changes were significantly differed among the tested cultivars and sampling times. In this respect, electrolytes (%), Na + , K + , inorganic phosphate (P i ), Ca 2+ , total soluble sugars (TSS) and total free amino acids (TFAA) concentrations were detected in leachate of fresh leaves and showed significant differences in response to the cultivars and sampling times. However, in this study, Alphonso, Bullock's Heart, Helmand, Taimour and Zebda cultivars of mango had the best result in their cold tolerance under the conditions of this study, which is not exactly in consistent with what the researcher found.

This experiment was conducted to found the connection between low temperature stress in vivo conditions (ambient-air temperature) and the changes in some physiological and biochemical events (leaf pigments and chlorophyll fluorescence) of mango trees in response to exposure to natural low temperature (cold). To verify this objective, 12 popular commonly mango cultivars (25 years old) which grown in private orchard in Fayoum Governorate, Egypt were selected for this study which carried out during the period from November to March of years; 2012 and 2013. The selected cultivars were: Alphonso, Baladi, Bullock's Heart, Helmand, Hindi Besennara, Mabrouka, Mestekawy, Nabeeh, Oweisi, Spates, Taimour and Zebda. Based on the obtained results, it can be stated that, chlorophyll (a) concentration in the leaves was significantly differed among the cultivars throughout the whole sampling times, in this respect, Helmand one gave the highest one while, and the highest one by sampling times was November one. The concentration of chlorophyll (b) was significant as effected by the effect of cultivars and sampling time recorded the highest value by the cultivar of Spates and December sample, respectively. Total chlorophyll concentration in the leaves reached its peak by the cultivar of Nabeeh and sampling time of December as compared to others. The both of Ewais cultivar and the sample of March showed the highest values of carotenoids concentration in the leaves. The levels of anthocyanin in leaves were significantly differed as affected by the cultivars and sampling times, indicating that the cultivar of Helmand and November sample recorded the highest values of anthocyanin in leaves. The greatest reductions in Fv/Fmratio were recorded at month of November and indicated that the reductions were in the order of Alphonso˃ Mabrouka˃Taimour˃ others. The effect of sampling time, cultivars and their interaction on Fv/Fm were significant, but small between some values of Fv/Fm.

This work aimed to investigate the influence of different levels of bean seed quality on germinability (laboratory study), growth, yield and its components (green pod and dry seed yield) under field conditions. To achieve this study, the seed lot of bean (cv. Giza 3) was manually separated into three classes; light (33.79-38.02g 100 -1 seeds; in 2005 season) and (34.39-37.13g 100 -1 seeds; in 2006 season); ungraded (37.70-42.85g 100 -1 seeds; in 2005 season) and (40.02-49.81g 100 -1 seeds; in 2006 season) and heavy (47.20-57.60g 100 -1 seeds; in 2005 season) and (48.75-57.13g 100 -1 seeds; in 2006 season). Under field conditions, seeds of bean were sown during two summer successive seasons of 2005 and 2006 at the experimental station, Faculty of Agriculture, Fayoum University, Egypt. The obtained data could be summarized as follows:High-weight class of bean seeds usually exhibited faster and more uniform rates of radicle emergence (as indicator of germination) than low-weight and ungraded ones. Seedling produced from heavier seeds had greater rates of QI, VI, length of radical hypocotyl and accumulation of fresh and dry weights than those from light seeds. The water uptake%, EC and the quantity of materials leached from the seed (Na, K, P i , sugars, free amino acids and A o 260 and A o 280 absorbing materials) during imbibition were inversely related to seed weight. It is suggesting that interferences existed during seed development or deterioration had occurred in the low weight seed.It can be noticed that seed quality of bean significantly affected field performance of bean plants and resulted in an increase of the studied plant growth traits (plant height, No. of leaves, No. of branches, leaf area leaf -1 , leaf area plant -1 , fresh and dry weights of leaves plant -1 , fresh and dry weights of branches plant -1 , and total fresh and dry weights of shoot plant -1 ) with increasing the level of seed quality class. It can be seen that there was a close relation between seed quality of bean and green pods yield and its components. In this respect, No. of green pods plant -1 , weight of green pod, green pod yield plant -1 and feddan -1 were increased as seed quality class was increased. It was found that bean dry seed yield and its components; empty and seeded pods plant -1 , total No. of pods plant -1 , grades of dry seeded pods, No. of seeds plant -1 , seed yield plant -1 and feddan -1 and seed index (100seed weight) was positively correlated with the class of sown seeds, the seeds which gave plants with high yield of dry seeds and its components were high in their quality and vice versa. It was shown that seed quality class markedly affected chemical constituents concentration of the different organs of bean plants

Under in vivo conditions (ambient-air temperature), the relationship between low temperature stress and the response of some different mango cultivars was monitored.Some biochemical events that occur following cold exposure of mango trees leaves were detected to evaluate their ability to acquire cold injury during exposure to low temperature. The cultivars of Alphonso, Baladi, Bullock's Heart, Helmand, Hindi Besennara, Mabrouka, Mestekawy, Nabeeh, Oweisi, Spates, Taimour and Zebdawhich grown in private orchard in Fayoum Governorate, Egypt were selected to verify this aim. This study was carried out during the period from November to March of during years; 2012 and 2013. The following results were stated: the detected leaf compositional changes were significantly differed among the tested cultivars and sampling times. In this respect, electrolytes (%), Na+, K+, inorganic phosphate (Pi), Ca2+, total soluble sugars (TSS) and total free amino acids (TFAA) concentrations were detected in leachate of fresh leaves and showed significant differences in response to the cultivars and sampling times. However, in this study, Alphonso, Bullock's Heart, Helmand, Taimour and Zebda cultivars of mango had the best result in their cold tolerance under the conditions of this study, which is not exactly in consistent with what the researcher found.