1993 Vol. 8, No. 1
Display Method:
1993, 8(1): 1-6.
Abstract:
With application of modern genetic theory and breeding technique, the paternal and maternal lines used for crossing have been established. The paternal line was developed from inbreeding, its inbreeding coefficient was 38-39%, While the maternal line was selected from generation among closed flock. The amount of egg laid by duck with age in 500days was as much as 266-276 in paternal line and 285-296 in maternal line. By mating between two lines and determining their combining ability of all combinations, it showed that the egg amount of optimum combination duck aged in 500 days was maximum to 329-344 which was 19 -16% above its parental lines. After establishment of proliferative system, there were 870, 000 ducks bred during 1988-1991 and the egg amount laid by 500 days age duck among these large scale was averaged to 305-310. In addition to breeding, It has been approached that: activity of enzyme extracted from duck embryo histological medium as standard for early line selection; main hereditary character data estimated as ecomonic index; the genetic feature for indio-shell egg heredity in duck breed; and the energy and protein necessity for these egg-laying ducks.
With application of modern genetic theory and breeding technique, the paternal and maternal lines used for crossing have been established. The paternal line was developed from inbreeding, its inbreeding coefficient was 38-39%, While the maternal line was selected from generation among closed flock. The amount of egg laid by duck with age in 500days was as much as 266-276 in paternal line and 285-296 in maternal line. By mating between two lines and determining their combining ability of all combinations, it showed that the egg amount of optimum combination duck aged in 500 days was maximum to 329-344 which was 19 -16% above its parental lines. After establishment of proliferative system, there were 870, 000 ducks bred during 1988-1991 and the egg amount laid by 500 days age duck among these large scale was averaged to 305-310. In addition to breeding, It has been approached that: activity of enzyme extracted from duck embryo histological medium as standard for early line selection; main hereditary character data estimated as ecomonic index; the genetic feature for indio-shell egg heredity in duck breed; and the energy and protein necessity for these egg-laying ducks.
1993, 8(1): 7-13.
Abstract:
The research on ecological agriculture is aimed at the macro-agriculture, with the consideration to economic, social and ecological benefits. For a long period, the grain production dominated in the cropping structure in Zhongmen, the aging and degenerated varieties are still used, and the fodder production has not been bringed to the attention. In order to improve the unreasonable cropping structure and low yield in a given area, the improved varieties of sweet potato, wheat and rice have been introduced, the traditional cropping system reformed, the different types of grainyielding models with one-ton harvest developped. As the result, the significant effect of increasing the yield and income has been achieved, which the grain yield in given area increased 34. 8%, the capitation grain pocessing amount increased 41.2%, the capitation income increased 1. 69 times.
The research on ecological agriculture is aimed at the macro-agriculture, with the consideration to economic, social and ecological benefits. For a long period, the grain production dominated in the cropping structure in Zhongmen, the aging and degenerated varieties are still used, and the fodder production has not been bringed to the attention. In order to improve the unreasonable cropping structure and low yield in a given area, the improved varieties of sweet potato, wheat and rice have been introduced, the traditional cropping system reformed, the different types of grainyielding models with one-ton harvest developped. As the result, the significant effect of increasing the yield and income has been achieved, which the grain yield in given area increased 34. 8%, the capitation grain pocessing amount increased 41.2%, the capitation income increased 1. 69 times.
1993, 8(1): 14-18.
Abstract:
Using the average daily temperature which is less than 20℃ for consecutive 3 days or more as the norm occuring "type 20" low temperature during autumn season, a periodic pattern modelled as Yi = 50.231+ 5.037Cosπ/9ti - 2.831Sinπ/9ti has been established via through the analysis of periodic pattern of initial days during autumn season from 1951 to 1989 in Fuzhou area. The dynamic change of low temperature and its influence on the production of late rice during autumn season in Fuzhou area has been analysed according to the model.
Using the average daily temperature which is less than 20℃ for consecutive 3 days or more as the norm occuring "type 20" low temperature during autumn season, a periodic pattern modelled as Yi = 50.231+ 5.037Cosπ/9ti - 2.831Sinπ/9ti has been established via through the analysis of periodic pattern of initial days during autumn season from 1951 to 1989 in Fuzhou area. The dynamic change of low temperature and its influence on the production of late rice during autumn season in Fuzhou area has been analysed according to the model.
Study on Heredity of Several Characters in Loquat I. Genetic Trendency of Fruit Agronomic Characters
1993, 8(1): 19-26.
Abstract:
The genetic trendency of fruit agronomic characters of 209 hybrid progenies from 14 cross combinations were analysed. The result showed as follow: Weight and shape of fruit, multiple quality belong to quantitative inheritance. Hybrid progenies had wide and continuous segregation, which showed the general rules of degenerated economic characters and the trendency of middle-taxis variance in hybridization and seedling multiplication of loquat. The heredity for color of peel and flesh is in accordance with a complicated pattern,and may be attributed to the incompletely dominant inheritance controlled by one pair or several pairs of gene. In this paper, the suggestions of selecting parent materials for cross-breeding in loquat were also made.
The genetic trendency of fruit agronomic characters of 209 hybrid progenies from 14 cross combinations were analysed. The result showed as follow: Weight and shape of fruit, multiple quality belong to quantitative inheritance. Hybrid progenies had wide and continuous segregation, which showed the general rules of degenerated economic characters and the trendency of middle-taxis variance in hybridization and seedling multiplication of loquat. The heredity for color of peel and flesh is in accordance with a complicated pattern,and may be attributed to the incompletely dominant inheritance controlled by one pair or several pairs of gene. In this paper, the suggestions of selecting parent materials for cross-breeding in loquat were also made.
1993, 8(1): 27-32.
Abstract:
The sensitivity of Phoma asparagi Sacc. from diseased asparagus of different areas in Fujian to thiophanate methyl was tested during 1989 to 1991. The results showed that strains from Changle and Putian possess high resistance to thiophanate methyl. Mycelia of these resistant strains can grow on PSA medium with 2000 ug/mL thiophanate methyl and the MIC value was hardly measured. Mycelia of the sensitive strains from Putian and Fuzhou, however, failed to grow on the PSA containg 10 ug/mL thiophanate methyl. In the area of Hunan in Changle County where asparagus has been cultivated for more than ten years and thiophanate methyl was used frequently, the ratio of resistant strains was as high as 100% in the field. The thiophanate methyl-resistance of strain F1 can be maintained at least 14 generations by the means of incubation on the biocide-free PSA medium. The cross resistance of two strains F1, L2 was found among benzimidazole fungicides, such as thiophanate methy 1, carbendazim and thiabendazole. However, these resistant strains are identical to sensitive strains, and all sensitive to Procymidone and guazatine.
The sensitivity of Phoma asparagi Sacc. from diseased asparagus of different areas in Fujian to thiophanate methyl was tested during 1989 to 1991. The results showed that strains from Changle and Putian possess high resistance to thiophanate methyl. Mycelia of these resistant strains can grow on PSA medium with 2000 ug/mL thiophanate methyl and the MIC value was hardly measured. Mycelia of the sensitive strains from Putian and Fuzhou, however, failed to grow on the PSA containg 10 ug/mL thiophanate methyl. In the area of Hunan in Changle County where asparagus has been cultivated for more than ten years and thiophanate methyl was used frequently, the ratio of resistant strains was as high as 100% in the field. The thiophanate methyl-resistance of strain F1 can be maintained at least 14 generations by the means of incubation on the biocide-free PSA medium. The cross resistance of two strains F1, L2 was found among benzimidazole fungicides, such as thiophanate methy 1, carbendazim and thiabendazole. However, these resistant strains are identical to sensitive strains, and all sensitive to Procymidone and guazatine.
1993, 8(1): 33-39.
Abstract:
Anagyrus daclylopii (Howard) belongs to family Encyrtidae (Hymenoptera: Chcidoidae). It is an important endoparasitic natural enemy of Nipaecoccus vastator (Maskell) by means of mono-parasitic or multiparasitic ways. At about 22. 8℃, its one generation takes 20-22 days. The longevity of the female adults is longer than that the male ones. When the temperature ranges 20- 23℃, the mean longevities of the mated female and male adults are 4. 02 and 3. 42days respectively. The female and male adults fed on water and 25% honey juice can survive fairly well under natural conditions, but the female adults reduce their own longevity owing to the behaviour of seeking host and ovipositing. The female adults can reproduce either sexually or arrhenotokously. A mated female adult lays 21. 5 eggs in average while an unmated one gives only 8. 1 eggs. This wasp species parasitizes in the second and third instar nymphs and female adults of the host. The female adults superparasitize seriously. The orders of both superparasitic degree and egg-wasted status are all as: most serious in female adults of Nipaecoccus vastator, then in 3rd instar nymph, and in 2nd instar nymph regardless in choice or nonchoice conditions. The frequency of superparasitized hosts reduces with the increase of host density but the egg number in the parasitized host is no different significantly in different host densities.
Anagyrus daclylopii (Howard) belongs to family Encyrtidae (Hymenoptera: Chcidoidae). It is an important endoparasitic natural enemy of Nipaecoccus vastator (Maskell) by means of mono-parasitic or multiparasitic ways. At about 22. 8℃, its one generation takes 20-22 days. The longevity of the female adults is longer than that the male ones. When the temperature ranges 20- 23℃, the mean longevities of the mated female and male adults are 4. 02 and 3. 42days respectively. The female and male adults fed on water and 25% honey juice can survive fairly well under natural conditions, but the female adults reduce their own longevity owing to the behaviour of seeking host and ovipositing. The female adults can reproduce either sexually or arrhenotokously. A mated female adult lays 21. 5 eggs in average while an unmated one gives only 8. 1 eggs. This wasp species parasitizes in the second and third instar nymphs and female adults of the host. The female adults superparasitize seriously. The orders of both superparasitic degree and egg-wasted status are all as: most serious in female adults of Nipaecoccus vastator, then in 3rd instar nymph, and in 2nd instar nymph regardless in choice or nonchoice conditions. The frequency of superparasitized hosts reduces with the increase of host density but the egg number in the parasitized host is no different significantly in different host densities.
1993, 8(1): 40-44.
Abstract:
This paper reviewed the earlier studies on Azoola cultivation, germplasm introduce and improvement in China. An effort made by National Azolla Research Center of Fujian Academy of Agricultural Sciences at germplasm improvement and breeding of Azolla including sexual hybridization of Azoola, re-establishment of Anabeana azollae with Anabaena free Azolla, radiation improvement of Azolla, back-cross breeding and characteristics of its progeny MH3-1 have been detailed. The authors also proposed that, more attention should be made on selecting fodder-using, salt-tolerant and rapid absorbing azolla varieties in further azolla breeding. In addition of above-mentioned methods, the introduce of pest-tolerant gene to Azolla, fuse of protoplast of Azolla, and gene transfer by electronmanipulation are recommended in order to obtain more effective achievement in Azolla breeding.
This paper reviewed the earlier studies on Azoola cultivation, germplasm introduce and improvement in China. An effort made by National Azolla Research Center of Fujian Academy of Agricultural Sciences at germplasm improvement and breeding of Azolla including sexual hybridization of Azoola, re-establishment of Anabeana azollae with Anabaena free Azolla, radiation improvement of Azolla, back-cross breeding and characteristics of its progeny MH3-1 have been detailed. The authors also proposed that, more attention should be made on selecting fodder-using, salt-tolerant and rapid absorbing azolla varieties in further azolla breeding. In addition of above-mentioned methods, the introduce of pest-tolerant gene to Azolla, fuse of protoplast of Azolla, and gene transfer by electronmanipulation are recommended in order to obtain more effective achievement in Azolla breeding.
1993, 8(1): 45-48.
Abstract:
A numerical method for estimating the parameters K, r, a of the Logistic curve is presented. It is based on the numerical integration and matrix least square method. The result shows that this method is simple and straightward, and fulfills the observed initial-value while the other methods are difficult to do so.
A numerical method for estimating the parameters K, r, a of the Logistic curve is presented. It is based on the numerical integration and matrix least square method. The result shows that this method is simple and straightward, and fulfills the observed initial-value while the other methods are difficult to do so.
