Ramie (Boehmeria nivea Gaud.), which can provide fodder in addition to bast fibre, was supplied with nitrogen in three different forms: as neem cake coated urea (NCU), lac coated urea (LCU) and standard urea, at rates of 60, 120, 180, 240 and 300 kg N ha−1 annually in four equal applications. The ramie was cut four times a year for two years. NCU increased fresh weight, leaf dry matter yield and leaf protein at almost every cutting compared with the other forms of nitrogen, and there was an indication of increased residual nitrogen in the soil. Leaf dry matter and protein content increased with increasing levels of nitrogen up to 180 kg ha−1. It is suggested that coating urea with neem cake makes it a better source of nitrogen for ramie leaf production.

Artificial defoliation of okra 4, 6 and 8 weeks after sowing generally delayed flowering, decreased plant height and stem girth at flowering and reduced the harvest duration. Pod length, pod diameter, mean pod weight and number of pods plant−1 were also decreased by defoliation but pod yield ha−1 was not.

The removal of leaves from the upper half of the stem only had a similar effect to complete defoliation whereas the removal of leaves from the lower half only had no significant effect, indicating that the leaves on the upper stem contributed more to growth and yield than those lower down. Significant time × degree of defoliation interactions occurred for most growth and yield parameters.

An experiment to investigate the effect of planting pattern, time of planting the cowpea, and insecticide application on the yield of intercropped cotton and cowpea showed that insecticide applied to the cotton controlled cowpea pests best when the crops were planted in alternating single rows. I n wet seasons, delayed planting of the cowpea reduced its yield but its performance was better in alternating single rows than in other planting patterns. In drier seasons, cowpea yield was unaffected by time of planting and yields were similar with alternating single or double rows. Cotton yield was reduced by 47% when the planting pattern was changed to a one cotton:two cowpea row configuration.

Extracted leaf protein is now used regularly as human food in several places. For preliminary, or domestic, trials the equipment used is inconveniently large. A miniature extraction unit, which does not depend on electricity, is described.

Experiments in two successive seasons showed that planting date and spacing of bulbs affected the seed yield of Sudanese onions, but not the number of branches and seed heads produced by bulbs. Yield per plant increased with increase in spacing, but closer spacing gave the highest yield per unit area. Later sowing depressed seed size, weight and yield.

This paper offers guidelines for the presentation of statistical material in scientific journals and project reports. Emphasis is given to the importance of planning a study so that the various components of statistical material can be linked to ensure the full efficiency of the work; if this is done well, the presentation of the results of the study, including the statistical components, can be achieved with greater ease.

Pot experiments with Malaysian rice variety Reyong-20 showed that sea water supplied at a concentration of 3 per cent increased yields of both grain and straw; a 6 per cent solution increased straw but not grain yields; yields were depressed at 9 and 12 per cent but tolerance of higher concentrations of sea water increased with age of the plants.

The crude protein contents of four Nigerian edible leafy vegetables were high, with values ranging from ao to 30% on a dry weight basis and maximum yields of crude protein ranging from 428 to 602 kg/ha. The percentages of leaf protein extracted ranged from 41 to 70%, whilst the highest yields of extractable edible protein varied from 199 to 332 kg/ha. The crude protein levels, as well as yields of extractable proteins, were slightly affected by the season of growth, but greatly by the age and species of plants.

Differences in the water and air regime of the germination environment may cause variations of 30% and over in the yield of barley, wheat and oats.

In sub-tropical India where 70% of the country's sugarcane is grown, companion cropping of wheat in autumn-planted sugarcane is beneficial. However, because the yield of sugarcane is reduced, farmers there are reluctant to adopt this cropping system in spite of the greater monetary gains compared with wheat-sugarcane sequential cropping. Application of 200 kg nitrogen ha−1 to sugarcane in two doses, two-thirds immediately after the wheat harvest and the remainder a month later, combined with irrigation at 75% available soil moisture during the summer months (April–June), produced cane yields similar to those from sole autumn-planted sugarcane, with an additional 4.8 t ha−1 of wheat.

A study was made of the effect of micronutrients such as boron, copper, zinc, manganese and iron, applied as foliar spray or directly to peat soil, on growth and yields of pepper under greenhouse and field conditions. Combinations of micronutrients were applied in two forms, as salts or as chelates. Results showed positive effects on yield and quality of red pepper, and soil chemical tests substantiated the results.

The results are reported of three field experiments conducted from 1955 to 1963 to investigate the effects of sunn green manuring in the sugar cane rotation. In a three-year rotation with sugar cane and wheat, green manuring twice was not superior to green manuring once, either in terms of sugar cane yield or the nitrogen and organic carbon status of the soil. Two experiments showed that the yield increase of cane was proportional to the weight of the green manure crop, irrespective of how the latter was disposed of, suggesting that the only factor with which yield increase was correlated was the weight of roots of sunn which were incorporated into the soil. The green manure effect is resolved into two components namely ‘green matter effect’ and ‘legume effect’, both of which are additive and nearly equal.

The yield of Chipewa variety of soyabean was investigated in relation to spacing and fertilizer levels on a range of paddy soils exhibiting good, medium and poor drainage. Under good conditions of drainage optimum yield was obtained at a density of 100,000 plants/ha and a fertilizer level equivalent to N—54, P2O5—54, K2O—75 and MgO—9 kg/ha. Under poorer conditions of drainage yield continued to increase up to a density of 162,000 plants and fertilizer levels of twice the above rates. Even under sub-optimal drainage conditions, however, satisfactory yields equivalent to about 1500 kg/ha were obtained from this variety.