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Transgenic rice lines that include barley genes have increased tolerance to low iron availability in a calcareous paddy soil 总被引:2,自引:0,他引:2
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The effects of glucose concentrations, different sugars and combinations of 2,4-D and kinetin on cell division and colony formation were examined in cultures of protoplasts isolated enzymatically from suspension cultures of Iris hollandica N6 medium supplemented with 1 mg/l 2,4-D, 1 mg/l kinetin, 200 mg/l casein hydrolysate, 250 mg/l proline, 0.3– 0.5 M glucose and 20 g/l agarose was suitable for cell division and colony formation. When colonies formed were transferred to hormone-free MS medium, many shoots were induced. In addition, when induced shoots were transferred to MS medium with 1 mg/l NAA, root induction was observed. A plant regeneration system from protoplasts of I. hollandica was thus established. 相似文献
46.
The transmission of tomato spotted wilt tospovirus (TSWV) by Thrips tabaci collected from leek was studied using the petunia local-lesion leaf-disc assay. After an acquisition-access period of 72 h given to newborn larvae up to 8 h old, the efficiency of transmission by adults was determined in three inoculation-access periods of 48 h. This efficiency varied for six T. tabaci populations from 0.7 to 11.6% in experiments using the Greek TSWV isolate GR-04. Males were more efficient transmitters than females (19 out of 176 versus five out of 494). Frankliniella occidentalis transmitted the same virus with a higher efficiency (34.8%). The transmission rate differed also among TSWV isolates, as shown in tests with four T. tabaci using two isolates. The virus was more efficiently acquired from infected leaf material of Datura stramonium than from that of Emilia sonchifolia . Plants of the latter species were more susceptible than Nicotiana tabacum in thrips transmission tests. 相似文献
47.
Taisei Nagata Mamoru Sameshima Taku Uchikawa Natsumi Osafune Takeshi Kitano 《Fisheries Science》2017,83(2):273-281
Episodes of summer mortality of the Kumamoto oyster Crassostrea sikamea are a major problem for its cultivation. Expression of the heat shock protein 70 (HSP70) is induced by various environmental stresses, including heat. We cloned and sequenced hsp70 complementary DNA from C. sikamea to investigate the relationship between hsp70 expression and heat tolerance in this oyster. Quantitative real-time polymerase chain reaction was performed using gill tissue dissected from oysters before and after heat shock for 1 h. The results showed hsp70 expression was faster and greater in oysters cultured at 20–22 °C than at 10–12 °C, and survival was lower among oysters cultured at 20–22 °C than at 10–12 °C. Moreover, heat tolerance was investigated by a 1-h pre-heat treatment, followed by exposure to heat shock conditions 5 days later. Survival was higher and hsp70 expression was notably lower in oysters that received the pre-heat treatment compared with those that did not. We conclude that a pre-heat treatment of only 1 h may be useful for inducing heat tolerance in C. sikamea, and that a low level of hsp70 expression after heat shock is an important index in selecting for high heat tolerance in these oysters. 相似文献
48.
Yutaro Sakai Nobuyuki Yagi Masahiko Ariji Atsushi Takahara Hisashi Kurokura 《Fisheries Science》2009,75(5):1079-1087
A demand system analysis was conducted to examine the substitute relationships between tuna and skipjack tuna in the Japanese
market. Data from the Annual Report on Family Income and Expenditure Survey from 1965 to 2006 were used for the analysis using
the almost ideal demand system (AIDS). Results suggest that skipjack tuna can be a strong substitute for tuna, while other
fish groups are not a clear substitute. Our analysis of substitute relationships among fish species in a market indicates
that this is a factor that should be considered for better fisheries resource management. For instance, even under a situation
where one fish species is underexploited, proper attention to its fishery management is necessary if the fish is a strong
substitute for another popular fish species in the market. 相似文献
49.
Takuya Nagata Hikari Dobashi Kazuaki Iijima Kazutoshi Ohyama 《Journal of Pesticide Science》2021,46(4):352
Crop field trials were conducted to investigate the residues of sprayed pesticides on the different sizes of tomatoes. Pesticide residue data in tomatoes varied due to different locations of the three crop fields selected and/or physicochemical properties of the three pesticides tested. The pesticide residue levels in the medium- and small-sized tomatoes were 1.5 and 2.4 times higher than the level in large-sized tomatoes under similar spray conditions, whereas amount of pesticides adhered per unit surface area were approximately equal among all three sizes of tomatoes. The results of this study suggested that the differences in pesticide residue levels were due to differences in the degree of specific surface area of each tomato size. Resultant residue data of medium-sized tomatoes demonstrated a proportional relationship between pesticide residue levels and the specific surface area of tomatoes. 相似文献
50.
Tamaki Masahiko Kobayashi Fumiyuki Suehiro Keisuke Ohsato Shuichi Sato Michio 《农业科学学报》2018,17(9):2024-2030
We investigated the possibility to reduce the usage of Blasin®Flowable (BF), a disinfectant inhibiting the germination and appressorium formation of Pyricularia oryzae Cavara conidia, by using carbon dioxide microbubbles (CO2MB). Germination was significantly inhibited by 10 000-fold diluted BF solution containing CO2MB generated by the decompression-type generator compared to CO2 millibubbles (CO2MMB) and CO2MB generated by the gas-water circulating-type generator. Appressorium formation in the 10 000-fold diluted BF solution containing both CO2MBs was less than that in CO2MMB. Scanning electron microscopy showed wrinkles and dents on the surface of conidia treated with 5 000-fold diluted BF solution containing both CO2MBs. Via transmission electron microscopy, we observed the expansion of the vacuole and the intracellular space and bloated or absent lipid granules in the conidia treated with BF solution containing both CO2MBs. Our results show that inhibition of the conidium germination and appressorium formation of P. oryzae Cavara by 10 000-fold diluted BF solution could be achieved by using the decompression-type CO2MB. 相似文献