頁籤選單縮合
題名 | 高粱臺中五號低發芽率之原因及解決方案 |
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作者姓名(中文) | 高德錚; | 書刊名 | 中華農學會報 |
卷期 | 137 1987.03[民76.03] |
頁次 | 頁55-71 |
分類號 | 434.157 |
關鍵詞 | 低發芽; 高粱; 臺中五號; |
語文 | 中文(Chinese) |
中文摘要 | 本試驗研究從採種流程來探討高粱臺中5號發育不良之原因,經檢查民國74年初設置於嘉義一帶之採種田作業後發現導致種子劣變之因素為: (1)種子劣變與種子活力、休眠性、後熟性及穗堆積熱無關。 (2)種子單寧含量在糊熟期時最高為0.275%,至枯熟期時已降至0.134%,此與種子罹病率增至39.4%有關。 (3)種穗上粒徑大於4.00公厘之大粒種子,含較高之單寧(0.191%)、罹病率低(29.8%)及發芽率高(86.5%),但在調製精選後此部分種子量從24.9%降至7.9%,相對地小粒種子(粒徑在3.35~2.28公厘)量從11.9%增至23.0%,且發芽率僅54.4%。 (4)採收過程使用之大型曳引機及聯合收穫機脫粒是造成種子破裂率從9.4%增至49.0%而發芽率由87.6%降至59.4%之原因。 (5)若以因果路徑分析法導出之貢獻百分比來估算種子發芽不良之因素為:①因種皮損傷而導致罹病者佔38.59%,②因種皮損傷但未罹病者佔32.38%,③種皮未損傷但罹病者佔15.22%,④種皮未損傷且未罹病者佔5.80%及⑤原因未明者佔8.01%。 試驗中進一步在植株噴灑巴拉刈,七天後,利用國產YS-2000D型高粱聯合收穫機直接收穫之。由結果顯示經巴拉刈處理後之植株及種子由於水分含量下降而增加收穫機之穀粒出口流量。完熟期時水分含量為25.3%,噴藥後可降至18.0%,此時收穫機行走速率0.5m/sec而脫穀筒轉速為500rpm或400rpm時,種子破裂率可降至9.3%及9.7%,而發芽率則提昇至83.3%及80.7%。據此,促進高粱臺中五號發芽率之方法為在黃熟期後植株噴灑巴拉刈,使種子水分提早降至20%以下,此時利用聯合收穫機進行採收,將可減少種子之機械性損傷致發芽率提昇到80%以上。 |
英文摘要 | The germination rate of hybrid sorghum cultivar Taichung No. 5 is usually low in the seed production in Taiwan. The cause of low germinability were regarded to be related with the events of anatomy, physiology and pathology of the seeds. (superscript 4, 5, 6, 11) However, all efforts failed to improve its germinability to pass germination test. This study, therefore, emphasized on the measures during seed harvesting, seed processing, seed drying, seed storage etc. Results were summarized as follows: 1. The low germinability of Taichung No. 5 was uncorrelated with its seed vigor, dormancy, post-ripeness and panicle storing heat. 2. The tannic acid content in the grain of Taichung No. 5 increased to 0.275% at mid-dough stage and down to 0.134% at full-ripen stage, while the pathogenic infection rate of seed was increased to 39.4% at harvest. 3. Taichung No. 5 could be divided into four groups by its seed size. The largest seed percent was 24.9% in invidual panical, and this parts of seeds obtained high tannic acid (0.191%), low pathogenic infection rate (29.8%), and best germinability (86.5%). Unfortunately, this part decreased to 7.9% during seed processing so that the germinability was down to 54.4% in average. 4. The seed breakage including damage of testa, endosperm and embryo changed from 9.4% to 49.0%. This breakage was due to mechanical damage by using tractor and combined harvester during de-seeding process. 5. Contribution percentage computed by path analysis was evaluated for the cause of low germinability in Taichung No. 5. It indicated that seed breakage resulted from mechanical damage was the major factor to cause pathogenic infection to induce the low germinability in Taichung No. 5. In advanced field survey, 18% of seed moisture was obtained by treating paraquat immediately after seed yellow ripe stage, as in comparison with 25.5% of seed moisture found in untreated control. It also indicated that mechanical damage could be reduced during mechanic harvesting process, as if the seed moisture was getting lower. Moreover, more than 80% of seed germination rate could be obtained from paraquat treated plot at full ripe stage, while the cylinder running speed and velocity of local sorghum harvester (13ps/2400 rpm) were set up by 400-500 rpm and 0.53 m/sec respectively. Therefore, using chemical desiccation of hybrid sorghum-Taichung No. 5 at full ripe stage to reduce seed moisture and then followed by mechanic harvesting process will be feasible for high germinability seed production. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。