Storage of vegetable seeds

Abstract

Several storage experiments of vegetable seeds have been carried out since 1950. One year storage was made in 1950, 51 and 56. Two series of long storage experiments were started in 1950 and 55 respectively. Experiments on the resistivity of seeds to heat was carried out in 1953_??_55. 1. At any relative humidity of the atmosphere, moisture contents of seeds were highest in bean, pea and soyabean, lowest in peanut and cucumber, and medium in spinach, onion, carrot, cabbage, etc. 2. Pea and bean produced hard seeds when their moisture contents failed below seven percent. 3. One year storage in 1950 and 51 was carried out in room temperature in desiccators which were conditioned to the relative humidities of 30_??_90 percent by saturated salt solutions. Same seeds were stored in paper bags, tin cans (no desiccant), tin cans (containing quicklime) and desiccators (contain-ing calcium chloride). Long period storage was carried out in paper bags, desiccators (no desiccant) and desiccators (containing calcium chloride) placed in room temperature, and desiccators (containing calcium chloride) and paper bags placed in a coldr oom of 0°C. These short and long storage experi-ments have shown that seeds of turnip, chinese cabbage, mustard, cucumber, watermelon, squash, tomato and radish belong to the type of longer life span, and those of carrot, edible burdock, welsh onion, onion, spinach, cabbage, lettuce, pea and bean belong to that of shorter life span. 4. In the long period storage, seeds stored in tin cans containing quicklime had shorter life spans than those in desiccators containing calcium chloride. This is due to the extremely small moisture con-tents of seeds of quicklime plot. Extreme reduc-tion of moisture contents of seeds is harmful to embryos. Seeds of quicklime plot and calcium chlo-ride plot had moisture contents of 2.4_??_4.1 percent and 5.4_??_9.3 percent respectively. The harmful ef-fect was significant especially in bean and pea seeds. In one year storage, however, the effect was hardly observed. 5. In cold room storage (0°C), several kinds of seeds lowered their germinability to some extent after two years. This is due to the large moisture contents of seeds of this plot (12.1_??_18.4 percent). This experiment has shown that cold storage in 0°C is less effective than room temperature storage in dry atmosphere. 6. Experiments on the resistivity of seeds to heat was carried out as follows: One to three grams of seeds conditioned to given moistures con-tents were put into 15cc test tubes. These tubes were sealed tightly and placed in the thermostat conditioned to temperature of 60 or 50°C. Onion and welsh onion seeds were tested also in 70° and 80°C. After certain periods the germinalility of these seeds was examined. Results have shown that re-sistivity of seeds to heat is generally in proportion to their longevity, that is, heat resistivity is great in chines, cabbage, eggplant, cucumber and shung-iku (chrysanthemum coronarium), small in onion, welsh onion, spinach and edible burdock, and me-dium in cabbage and carrot.