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This work was conducted in 1955-1956 at Nanking (32°03'N'),China.800 rice varietiesnative to China were collected and sowed under the day-length of 9.5,11.5,12.5,13.5,and 18hrs.and natural day-length as control.Bamboo frames with black oil-cloth were used to shutoff day-light for short-day treatments.While electric lamps were used to lengthen naturalday-length for long-day treatments.Seeds soaked with water for 36 hours and vernalized at25℃ for 12 days and then,sowed on May 20:It was demonstrated that even under... This work was conducted in 1955-1956 at Nanking (32°03'N'),China.800 rice varietiesnative to China were collected and sowed under the day-length of 9.5,11.5,12.5,13.5,and 18hrs.and natural day-length as control.Bamboo frames with black oil-cloth were used to shutoff day-light for short-day treatments.While electric lamps were used to lengthen naturalday-length for long-day treatments.Seeds soaked with water for 36 hours and vernalized at25℃ for 12 days and then,sowed on May 20:It was demonstrated that even under warm and proper short-day conditions—commonly9,5 to 11.5 hours of exposure to light for 24 hrs.cycle—the length of growth periods (fromsowing to heading) for different rice varieties varied from 42 (The shortest one Changjidao,a native variety of changji,Xinjiang) to 88 days (The longest one,Hongzuijia,a nativevariety of Fenghua,Zhejiang).This characteristics of rice varieties was denoted by the term“short-day growth period”.According to length of growth period under short-day conditionwe divided the rice varieties into 10 classes as follows:The rice varieties were thus classified and the result was listed'in table 1.It shows thatthe rice varieties from South China varies from B_1 to B_(10);the Middle and South-western Chinavarieties,from B_2 to B_9;the North China varieties,from B_2 to B_7;the North-eastern Chinavarieties,from B_2 to B_6,and the North-western China varieties,from B_1 to B_3.This resultstrongly indicates that the property of “short-day growth period”of a rice variety is closelyrelated to the climatic conditions of its original habitat.In regions of high latitude or plateauwith high altitude,usually accompanied with shorter growing season,the rice varieties withshorter length of growth period would be suitable for cultivation;while in plains of lowlatitude,usually followed by longer growing season,the rice varieties with either shorter orlonger length of growth period might be recommended for use.The earliness of maturity of a rice variety is fully determined by its “short-day growthperiod”and response to day-length.Thus we had in Nanking: L,response to day-length;B,“short-day growth period”.The yield components,especially the number of spikelets per panicle varied greatly amongthe rice varieties of different response to day-length under the conditions of experimentaltreatments.The data show that for very weak response type of rice varieties,the averagenumber of spikelets per panicle varied from 9.5% to 105% (take average number of spikeletsper panicle under 11.5 hrs.of light exposure in 24 hrs.cycles as 100%) under the testedrange of day-length;for weak type 90%-120%;for moderate type 0-124%;for strong type0-218%;and for very strong type 0-150%.Thus,it is evident that the stronger the varietyresponds to day-length,the greater,the variations of the number of spikelets per panicle wouldbe.This was further confirmed by the evidence that rice varieties of L very weak andL weak types always show greater ability of adaptation to changed conditions.Hence,moreattention should be paid to rice varieties of these two types for specialists of seed improve-ment.It should be emphasized especially for seed improvement of subsp.Keng,because onlya few varieties now existed are of L very weak and L weak types with medium “short-daygrowth period”.Such types of rice varieties are urgently needed in present crop-production. 用800个中国水稻品种试验的结果指出:不同地区原产的品种不但对光照长度的反应特性不同,而且在短日照下的生育期也不同。这种特性称为短日生育性。北方的品种短日生育性较小;南方的品种从小到大都有。品种成熟期的早晚是其光照长度反应特性和短日生育性在一定环境条件下的具体表现,改变环境条件时,早晚熟的顺序随之改变。对光照长度反应弱的品种一般产量变化小,适应力大。试验结果得出各地区品种的光长反应特性和短日生育性。 This paper aimed resule of analysing climatic and ecologic condit-ons of soybean, in order to map out the regionalized target. According to this Xinjiang was divided in to the most suitable、 the suitable and unsuitable soybean planting areas and 13 subordinate areas. Referring "The National Soybean Vanriety Ecotype Joint Test" (1980-1982) the suitable soybean varieties for 13 subordinate areas have, been found. 本文以新疆大豆气候态生试验结果,订出区划的指标;进而把新疆划分成最适宜、适宜、不适宜大豆种植区,及下属十三个亚区。并从1980年—1982年“全国大豆品种生态型联合试验”中找出了适合各亚区种植的大豆品种。 Xinjiang Wheat(T.petropavlovskyi Udacz.et Migusch.)is an ende-mic rare species in Xinjiang Uygur Autonomous Region of China.Cyto-logical and genetical investigations have been made on this wheat spcci-es.Cytological analysis of the different interspecific hybrids F1 showsthat some chromosomes of Xinjiang wheat differed from those in AABB-DD genomes of T.aestivum,especially in A or B genomes.Plant types similar to T.polonicum and T.aestivum were appeared in theF_2 generation of the crosses between... Xinjiang Wheat(T.petropavlovskyi Udacz.et Migusch.)is an ende-mic rare species in Xinjiang Uygur Autonomous Region of China.Cyto-logical and genetical investigations have been made on this wheat spcci-es.Cytological analysis of the different interspecific hybrids F1 showsthat some chromosomes of Xinjiang wheat differed from those in AABB-DD genomes of T.aestivum,especially in A or B genomes.Plant types similar to T.polonicum and T.aestivum were appeared in theF_2 generation of the crosses between Xinjiang wheat and tetraploid spe-cies.It is therefore suggested that Xinjiang wheat were evolved fromnatural cross of T.aestivum with T.polonicum and then derived frombackcross with T.aestivum 将“新疆小麦”(T.petropavlovskyi Udacz.et Migusch.)与不同小麦种杂交,观察杂种 F_1减数分裂期的染色体行为,发现它与普通小麦(AABBDD)的杂种有57.8%以上细胞配对正常,有37.2%的细胞具1~9个单价体,其中多数具1~2个单价体,说明“新疆小麦”的染色体组型基本为 AABBDD,但其中有一对染色体已与普通小麦不同。当它与含有 AABB 组的四倍体小麦杂交时,五个组合中有19.4~32.6%细胞具8~13个单价体,其中多数具9条单价体。说明“新疆小麦”在 AA 组或 BB 组中有一对染色体与二粒系小麦不同。本文研究了“新疆小麦”与圆锥小麦、硬粒小麦、东方小麦等杂种后代穗形的分离,发现这三个组合中 F_2各自分离出2.9%、10.8%和40.0%的波兰小麦类型,同时在前两个组合中也分离出普通小麦类型。由此推论,波兰小麦和普通小麦可能参与了“新疆小麦”的形成。
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