Pre-broadcasting treatment for better groundnut harvest
Controlling number of tillers for increasing rice yield
Method of preventing cotton plant with non-blooming buds
Rice blast diagnosis
Inter-cropping corn and chili for increased production
Inter-cropping of cotton and melon (Cucumis melo)
Honey bee - a good guard against bird damage to grape
Inter-cropping for pest control in cotton
Rape seed-cotton rotation
Groundnut is usually planted by broadcasting. Before broadcasting the seeds they are treated in three steps. First the groundnut is dried in the sun and graded. Drying seeds before peeling off can improve seed vigor. Usually the skin of the peanut is peeled off 4 days before broadcasting and then large size seeds are selected for broadcasting.
Then the seeds are soaked in cold water for 12-14 hours followed by again soaking in lukewarm water (35° C) for 2 minutes. The soaked seeds are then put in a bucket and a wet grass film is used to wrap them closely. The bud will sprout after 20 hours.
The third step is dressing the seed by pesticide. This is done by evenly splashing ammonium molybdate desolved in lukewarm water on the seeds and then dressing the seeds with duojunling (a local pesticide) in order to prevent disease and pests. For 50 kg of seeds 100 g ammonium molybdate and 250 g of Duojunling with a 25% concentration is required.
Rice yield can be increased by 30-40% by controlling the number of tillers. In this method the water is drained from the paddy fields so that the soil is exposed to the sun and allowed to dry till fissures appear. The fields are then irrigated again and this procedure is repeated several times till the number of tillers is only 80% of normal tillers of a variety. If there is more rain in tropical areas and there are less sunny days, there is no need to irrigate again after draining water until two leaf stage. The paddy field should be kept dry and wet alternately. The method produces 20% more grain bearing ears compared to the rate without the use of this method.
Another method, which can increase rice yield by 30%, is by frequent irrigation to the depth of two leaves. After the two leaf stage the field should is kept wet and dry alternately. In fertile clay soils more sunshine is needed other wise in sandy and less fertile soils long exposure to sunshine is not needed.
A successful method to solve the problem of cotton plants bearing non-blooming buds is to spray on the leaves a 0.1 % boric acid and 0.2 % borax hot mix diluted in cold water. The rate of spray is 6,975 liters/ha. The spraying is done during seedling stage, bud stage and blooming stages, respectively.
There are two methods for diagnosis of rice blast in advance. One method is to take 6 rice leaves with some spots on them from the field. Put them in a bowl with a piece of wet cotton. A bowl is closed with a plastic cover. Put the bowl in an oven at 24°C for 24 hours. Then take the leaves out of the bowl and check whether there is a gray mould on the back of the leaf. If there is, then it can be confirmed that the rice plant in the field is suffering from blast.
Another method is to take the 6 rice leaves with some spots from the field. Bind them and hang them above hot water at 40°C in a bottle. Then close the bottle for 24 hours. After that, check at the back of the leaves. The appearance of gray mould on it shows that the rice field will be attacked by blast. Preventive measures should be taken as early as possible.
11 Compiled by Mr. Li Xuemin, Chongzhou Agriculture Forest Academy of Sciences, Hebei.
Inter-cropping corn and chili can enhance land productivity. The corn production not only remains the same but the chili crop also gets good profit.
For land preparation, it is tilled to 25 cm depth and spread with organic manure. Now a days phosphorus and nitrogen (1:2/3) are also applied to the soil. The corn is planted at a row spacing of 100 cm × 15 cm with a plant density of 4500 rows per 0.15 ha. Two columns of chili are planted between corn in 30×30 cm spacing. The density of chili is at a rate of 4500 rows per 0.15 ha.
Now a day fertilizer is sprayed during crop growth. Weeding and pest control before corn cobs are formed require special attention. To promote chili to ripe old corn leaves should be removed during the growing stage of the corn.
The heights of corn and chili plants are quite different. Lower leaves of corn shadow the chili, which is beneficial to it. On an average about 77 corn leaves are in 100-160 cm space, but chili occupies 60-80 cm space. This is a good arrangement to give sufficient light to chili. The corn production under this intercropping is same as of solo crop. Thus income from chili becomes extra. However, the method is suitable in summer season of semi-humid regions only as enough light and water are available at the same time.
12 Compiled by Lui Xiaowen and Pong Shuping, Agriculture Extension Station, Zhibo, Sandong and Jia Fusheng and Sun Chuandian, Agriculture Extension Station, Bianhe, Sandong, China.
For this inter-cropping arrangement, plant cotton in wide columns (80 cm) alternating with narrow columns (50-55 cm), with row spacing of 28-30 cm with a density is 3500 rows per 0.15 ha. Melon is planted in the space between wide columns of cotton with a row distance of 60-70 cm and a density of 800 rows per 0.15 ha for melon.
For good land preparation, in the winter season during plowing apply organic manure at a rate of 2500-3000 kg/ha, calcium phosphate 40-50 Kg/ha and urea 15-20 kg/ha. Then rake the soil for sowing in April in the tropical regions of Sandong province of China.
Pre-treat the cotton seeds in hot water at a temperature of 75°C for 2-3 days before sowing. The land is then covered with a plastic film after sowing. If the soil is dry it needs to be watered 1-2 liter/hole before sowing.
Select melon seeds of medium variety with high yield. Melon is sown at the same time with cotton. Put 2-3 melon seeds in each hole and cover with 2 cm of soil.
Cotton blooming and ball formation stage
By controlling the cotton density, it grows faster and promotes the growth of melon. It needs about 80 days for melon to ripen from the time of sowing. During this period cotton grows slowly and does not need too much water and fertilizer. This creates a good growing condition for melon.
Thinning out of the cotton seedling is required at two leaf stage. Control of the cotton pests such as aphid, thrips and cutworm etc also. The soil should be loosened to keep the moisture intact and to promote growth. If melon grows too fast, only 3-4 branches and 3-4 melons should be kept. Its head and other branches should be cut. It is necessary to control pests such as powdery mildew.
Melon ripens in June- July. It should be harvested on time, since cotton needs more nutrition at this time. Chemical liquid should be sprayed twice to foster the growth of strong cotton seedling after it has 5-8 buds. The first spraying should be done at the end of June and the second spraying should be in the middle of July. Take out plastic film in the last ten days of June, and work the soil to loosen it in the spaces between the cotton columns.
It is necessary to spray 10-15 kg urea before the 10th of July and around the 20th-25th of July. The head of the plant should be cut at the same time when the pruning is done during the first week of August. Attention should be paid to drainage, to loosening of the soil and to timely pest control.
Since both cotton and melon are drought-resistant and have different growing periods, inter-cropping the two can have high economic benefits. Natural resources such as land, light and water are used very economically. This technology is well suited to the rainfed mountain areas. However the intercropping is not suitable for cotton and melon varieties that have long growing period.
Birds like to eat ripe grapes. Honeybee is a good guard against this damage. If beehives are put in the grape orchards during their grape maturity period, it very successfully protects the grape from bird damage. Bees attack birds, when they come to eat grape. According to local experience about 30 beehives/ha of orchard is enough for complete damage control.
Plant sorghum on both sides of a cotton furrow at intervals of 2 m. This is found to prevent pink ballworm in cotton. Intercropping cotton and sorghum does not effect the cotton growth and protects cotton in rainstorms.
Plant one rape seed column at an interval of every 11-12 cotton columns. Before cotton is sown, the rape seed should be uprooted or plowed under the soil to attract the natural enemy of cotton i.e. the aphid. It also increases the organic fertilizer content of the soil.