-->Special Subject: Physiology and Cultivation of Fruit Trees

Effects of pipeline trunk transfusion and drip on walnut growth and fruit

2016/7/12 14:36:42

We studied the integrated management of water and fertilizer pesticide on walnut cv. Liaohe with pipeline trunk transfusion and drip irrigation technology, in order to achieve the goal of water conservation, efficient use of fertilizers and pesticides, get better yields and improve quality so as to explore a new way for the quality and efficiency of walnut. We Compared with the soil fertilization treatment and conventional management,and Determined the leaf SPAD, leaf area, new shoots length, new shoots diameter, soil water content, yield per plant, single fruit weight, kernel rate, black fruit rate, and so on. The result showed that compared with soil fertilization treatment and conventional management, the pipeline trunk transfusion and drip irrigation treatment increased the leaf SPAD value by 20.39% and 75.27%, leaf area increased by 18.27% and 51.54%, new shoots length increased by 7.03% and 13.73%,new shoots diameter increased by 21.92% and 27.14%, trunk girth increased by 20.52% and 24.28%, soil water content of 0-20 cm soil layer increased by 8.63% and 8.52%, yield per plant increased by 21.62% and 73.08%, single fruit weight increased by 14.55% and 23.53%, the kernel rate increased by 11.40% and 12.44%,the black fruit rate decreased by 88.97% and 91.74%, respectively. It showed that pipeline trunk transfusion and drip irrigation technology could greatly promote the growth of tree, improve the yield of walnut and walnut fruit quality. This mode could strengthen the resistance ability of walnut, reduce the black fruit rate, and achieve the goal of high yield and stable yield of walnut. This experiment provides a sufficient basis for popularization and application of pipeline trunk transfusion and drip irrigation technology.

Reproductive biology of endangered plant Actinidia chrysantha

2016/7/12 14:36:42

At present,reproductive biology has become one of the important research field of conservation biology of endangered plant, Actinidia chrysantha was one of endangered species in Actinidia genus, but there was no reproductive biology related reports about it till now. In this study, took wild A. chrysantha plants which distributed in Hua-ping National Nature Reserve as test material, its floral organ and fruit shape were measured with a vernier caliper; based on field observations recorded its phonological period, flower visiting insect, blossom and fruiting habit; determine its pollinators by artificial pollination and bagging experiments; through field sowing test, determine the seed reproductive capacity. The results showed that phenological characters of A. chrysantha were different with the altitude varying. At lower altitude area its flowering in the middle or late May, while at the higher altitude area its flowering in the late May to early June, flower season lasted for 7-10 d; fruit ripening in late September to early October of every year; spray rate of the male plants was 76.5%, fruit branch rate of female plants was 61.9%, the fruit shape was long column, short column or oval, the average weight of single fruit was 7.34-27.53 g, the maximum fruit weight was 35.0 g; its pollinated by insects and wind in common, the main pollinators including Apidae, Prpductotrupidae, Rhiniinae, Syrphidae, Fulgoridae, Ctenacroscelis of Tipulidae insects etc.; its germination rate of seeds was low, germination rate of three tested populations Huaping, Chetian of Ziyuan County and Gupo Mountain of Hezhou were 17.5%, 15.36% and 0, respectively. In the 4 kinds of seed processing method, the treatment that the seeds was stored at 0-5 ℃ in the refrigerator and before sowing with 1 500 mg·L^-1 gibberellin(GA₃)soaked for 2 h, had the highest germination rate(22.67%). In summary, there was no pollination barrier in the reproductive process of Actinidia chrysantha, low germination rate may be an important cause of A. chrysantha endangered. Therefore, this study provides scientific basis for the protection of A. chrysantha germplasm resources. At present,reproductive biology has become one of the important research field of conservation biology of endangered plant, Actinidia chrysantha was one of endangered species in Actinidia genus, but there was no reproductive biology related reports about it till now. In this study, took wild A. chrysantha plants which distributed in Hua-ping National Nature Reserve as test material, its floral organ and fruit shape were measured with a vernier caliper; based on field observations recorded its phonological period, flower visiting insect, blossom and fruiting habit; determine its pollinators by artificial pollination and bagging experiments; through field sowing test, determine the seed reproductive capacity. The results showed that phenological characters of A. chrysantha were different with the altitude varying. At lower altitude area its flowering in the middle or late May, while at the higher altitude area its flowering in the late May to early June, flower season lasted for 7-10 d; fruit ripening in late September to early October of every year; spray rate of the male plants was 76.5%, fruit branch rate of female plants was 61.9%, the fruit shape was long column, short column or oval, the average weight of single fruit was 7.34-27.53 g, the maximum fruit weight was 35.0 g; its pollinated by insects and wind in common, the main pollinators including Apidae, Prpductotrupidae, Rhiniinae, Syrphidae, Fulgoridae, Ctenacroscelis of Tipulidae insects etc.; its germination rate of seeds was low, germination rate of three tested populations Huaping, Chetian of Ziyuan County and Gupo Mountain of Hezhou were 17.5%, 15.36% and 0, respectively. In the 4 kinds of seed processing method, the treatment that the seeds was stored at 0-5 ℃ in the refrigerator and before sowing with 1 500 mg·L^-1 gibberellin(GA₃)soaked for 2 h, had the highest germination rate(22.67%). In summary, there was no pollination barrier in the reproductive process of Actinidia chrysantha, low germination rate may be an important cause of A. chrysantha endangered. Therefore, this study provides scientific basis for the protection of A. chrysantha germplasm resources.

Submergence tolerance of ‘LD-1' stock-grafted Actinidia deliciosa Miliang 1

2016/7/12 14:36:42

Actinidia deliciosa Miliang 1, cultivated by a research team of Jishou University, Hunan Province, is a fruit tree with high output and high nutrition value but poor flood resistance, so the research on water stress is of great importance for its promotion. Some professors attempted to use Actinidia ‘LD-1' as rootstocks to improve the submergence tolerance of A. deliciosa Miliang 1 in recent years. But in order to further reveal the submergence tolerance of ‘LD-1' stock-grafted A. deliciosa Miliang 1 from the physiological perspective, we selected the Miliang 1 seedling stock-grafted A. deliciosa Miliang 1 and the ‘LD-1' stock-grafted A. deliciosa Miliang 1 as experimental materials, which were transplanted to flowerpots outside the laboratory at Jishou University in December, 2013. When the condition permitted, we treated the roots of those two materials with flood and non-flood group respectively in July, 2014. And in each group, we had 3 fruit trees for experiment. Besides recording morphological change in leaves of two experimental materials after 0, 2, 4, 6, 8 and 10 d waterlogging(both flood and non-flood group), we also tested other 5 physiological indices——soluble sugar content by anthrone colorimetry, malondialdhe(MDA)by thiobarbituric acid(TBA)spectrophotometric, chlorophyll content by spectrophotometry, soluble protein content by coomassie brilliant blue(CBB)G-250 and superoxide dismutase(SOD)activity by nitroblue tetrazolium. The results were as follows:(1)When the roots of Miliang 1 seedling stock-grafted A. deliciosa Miliang 1 waterlogged, soluble sugar content in leaves of those flooded tree increased very significantly(P<0.01)6 d later compared with those non-flooded group; the content of malondialdehyde(MDA)also had a significant increase(P<0.05)after 8 d; and there was no significant change in chlorophyll content and soluble protein content; the activity of superoxide dismutase(SOD)increased significantly(P<0.05)6 d later while it had no significant change after 8 d; otherwise, after 2 d waterlogging, we observed there were a small amount of leaves wilting and all leaves died after 10 d.(2)However, the damage to ‘LD-1' stock-grafted Actinidia deliciosa Miliang 1 appeared weak. Except the content of soluble sugar increased significantly(P<0.05)4 d later, the content of malondialdehyde(MDA), the content of chlorophyll,the content of soluble protein and the activity of superoxide dismutase(SOD)had no significant change; in addition, the leaves of ‘LD-1' stock-grafted A. deliciosa Miliang 1 did not wilt or die 10 d later, it also seemed normal after 30 d water stress. The results, on the one hand, obviously showed that the flooding resistance of ‘LD-1' stock-grafted A. deliciosa Miliang 1 was higher than that of Miliang 1 seedling stock-grafted A. deliciosa Miliang 1; the submergence tolerance of A. deliciosa Miliang 1 was enhanced significantly by Actinidia ‘LD-1' stock. On the other hand, this research also provides a theoretical basis for the usage of ‘LD-1' rootstocks on A. deliciosa Miliang 1.

Resistance physiological indexes of different walnut varieties after infected by Fusarium solani

2016/7/12 14:36:42

Juglans sigllata, a commercial crop, is widely planted in Liangshan prefecture of Southwest China. Liangshan prefecture is a major traditional growing area of J. sigllata and has an unique advantage for walnut industrial development because of its good conditions of soil, solar-thermal and source of water. Currently there are 2.7 hm² walnut, contributing to an important incomes for farmers. In April 2013, numerous J. sigllata were found infected with the root rot in the Muli County of Liangshan prefecture. Complications include dried leaves, dead brachces, and even death. According to the cultural characteristics, the fungus was primarily identified as Fusarium solani. To analyze the impact of host resistance physiological index of walnut root rot caused by F. solani, in this study, three different walnut varieties including Juglans sigllata, Mianyang walnut and No. 2 of Xinjiang walnut were the samples, and their morbidity situations and six changes of the physiological indexes including MDA, soluble sugar, POD, PPO, SOD and CAT were further detected after inoculated of Fusarium solani respectively. The results showed that the morbidity of Juglans sigllata was up to 100%, and the morbidities of Mianyang walnut and Xinjiang walnut were 23.33% and 16.67%, so it turned out that J. sigllata belonged to highly infected varieties, while the other two were disease-resistant varieties. During the fifty monitoring days, the leaf physiological indexes of the controls showed fluctuated and no obvious difference. But the content of soluble sugar of the experimental group droped rapidly over time, and the content of MDA and POD activities performanced rising trends overall, for SOD and PPO activities, it rose firstly and then droped. Moreover, the differences among the five Indexes of the study were significant while it was irregular to CAT activity. The correlation analysis indicated that the contents of soluble sugar and MDA, the activities of SOD, POD and PPO could be used as the standards to evaluate the resistance abilities of different walnut varieties. This paper provides important references to the study on mechanism of walnut root rot and improvement of resistance abilities.

Effects of different storage conditions on changes of bitter substance of “Shatian” Pomelo

2016/7/12 16:15:55

The “Shatian” Pomelo(Citrus grandis Osbeck)was native to Guangxi, rich in nutrition and for hypertension and diabetes patients to eat. In recent years, there were many problems in the industry, such as quality decreased, smell and bitter generated. The “Shatian” Pomelo were stored under ambient temperature with film(A), ambient temperature without film(B)and 4 ℃ without film(C). Naringin, limonin and nomilin contents in different sues of fruits were determined during storage by high-performance liquid chromatography. The results showed that Naringin as main bittering substance of Shatian” Pomelo was distributed in the albedos and segment membranes. Limonoids mainly distributed in the seeds and flavedos, and nomilin mainly distributed in the seeds. Changes of bittering substance contents were different during storage under three storage conditions. The naringin content slightly increased during storage, while limonin and nomilin contents declined overall with a minor fluctuation. The contents of limonin and nomilin in juice sac increased firstly and then decreased. On the 30th day of storage, A, B and C storage conditions of naringin contents in juice sacs were(0.139 ± 0.006),(0.190 ± 0.009)and(0.194 ± 0.019)mg·g^-1 respectively and limonin contents were(47.28 ± 1.91),(33.64 ± 1.90)and(84.19 ± 5.56)μg·g^-1 respectively. Comparing with the A and B storage conditions, the contents of naringin and limonin of fruit juice sac under 4 ℃ low temperature storage(C storage conditions)were the highest. On the contrary, the contents of naringin, limonin and nomilin in flavedos, albedos, segment membranes and seeds were the lowest under C storage condition. This study provides theoretical guides for storage of postharvest “Shatian” Pomelo.