Mon O45 at rates of 4 and 6 kg./ha. was shown to increase total dry matter in the stem of the sugarcane variety M13/56, optimum response occurring at 9–12 weeks after application. The increase in dry matter was mainly due to an increase in sucrose, since the chemical had no effect on fibre and decreased reducing sugars. The site of action appears to be in the top 16 internodes. Possible modes of action of the chemical are discussed.

Visual symptoms of deficiencies of nitrogen, phosphorus, potassium, calcium, magnesium, sulphur and boron on pyrethrum are described, and compared with those observed previously on other species of chrysanthemum.

The important interactions in a 2-year maize trial were population × location, location × year and population × year × location, and our analyses suggest that eight locations, two years and three replications will allow the detection of a 5% differential in yield. The most effective way of obtaining the true value of a variety is by increasing the number of years, and the least effective is by increasing the number of replications. Since locations can be effectively substituted for years, increasing the number of locations will expedite the release of improved cultivars.

Before an innovation can be judged as superior to existing technology, its relevance should be jointly evaluated by researchers and farmers by testing the proposed practice in a farm environment. Using a proposed maize technology as an example, it is demonstrated how site-related and management variables can be used to quantify the factors influencing actual yields on farmers' fields. Similarly, economic and management analysis of the practice provides an estimate of the probability of the farmer being better off by using the technology. The integrated analysis of the practice provide insights for the design of problem-oriented research projects.

Nitrogen-atrazine combinations were significantly more effective in stimulating higher yield components of sorghum and depressing yield components of striga than sole treatments of either nitrogen or atrazine. Over all treatments nitrophoska at 129 kg N/ha in combination with atrazine at 1.75 kg/ha gave 224, 180, 155 and 151% increases in yield components over the control for head, straw, 1000 grain weights and plant height of sorghum, and a decrease in 83, 88 and 90% of striga density at 8, 12, and 16 weeks from sowing the sorghum. The synergistic effect of nitrogen-atrazine is demonstrated.

The effect of different soil temperatures on the development of young eggplants was examined at extreme seasonal air temperatures. In winter, rising soil temperatures accelerated growth, but lowering the soil temperature in summer had no effect and extremely high soil temperatures caused very poor plant development.

Two of the most common criticisms over the widely used Palmer Drought Severity Index (PDSI) is that it cannot be calculated at different time scales and it is not as spatially comparable as other Standardized Drought Indices (SDI), such as the Standardized Precipitation Index (SPI). Therefore, the hypothesis that the PDSI may be transformed into a multi-scalar index sharing the same normalized nature of others SDI has been proposed in the scientific literature. This hypothesis was extensively evaluated in this study by statistical methods largely used to assess and improve the performance of others standardized drought indices (e.g. SPI). In general terms, these methods evaluated the ability of the transformed/probability-based Palmer's Index to approach the standard normal distribution. The strategy of basing the selection of a distribution for calculating such an index on its performance within the range of typical drought and flood events was adopted. The testing region was the State of São Paulo, a tropical-subtropical region of Brazil. Time scales ranging from 1- to 12-month and Available Water Capacity equal to 50, 100 and 150 mm were also considered. A computational algorithm for calculating the new version of the Palmer's index is also provided. The Generalized Logistic distribution with parameters estimated by the maximum likelihood method is recommended to calculate the new index. The results of the normality tests are consistent with the above-mentioned strategy. From a scientific standpoint, the results support the hypothesis of this study. Therefore, we conclude that the new Standardized Palmer Drought Index (SPDI) is capable of meeting the normally assumption under tropical-subtropical climatic conditions of Brazil. In other words, the new SPDI has shown to be capable of representing floods and drought events in a similar probabilistic/normalized way. This conclusion holds true for time scales ranging from 1- to 12-month and Available Water Capacity equal to 50, 100 and 150 mm.

In India, sorghum is grown during the post-rainy season on Vertisols with stored soil moisture. As water stress towards the end of the growing season is believed to be a major cause of poor yields in these crops, an experiment was carried out involving five sorghum genotypes and four sowing dates with and without irrigation.

Supplementary irrigation with 40 mm of water in the earliest sown crop increased grain yields by 24 and 26% in 1979 and 1982, respectively, while irrigation with a total of 120mm water in the latest sown crop increased yields by 87 and 60% compared with the corresponding dryland crops. Early sowings always resulted in better stover and grain yields irrespective of irrigation treatment. Grain yields of hybrids were similar to those of the cultivars but their stover yields were less. The post-rainy season cultivar SPY 86 gave the best grain yield across sowing dates. The widely grown post-rainy season cultivar M 35–1 yielded less but produced more stover and its yields were more stable. The importance of the stability of grain and stover yields and of evaluating the materials for more than one date of sowing in selecting sorghums for the post-rainy season is discussed.

The object of the study was to find whether loss during combine harvesting was correlated with pod shattering propensity of soybeans. Mechanical pod shattering methods tested included vibration, impact, centrifugation, pod traction and compression. The influence of variety and moisture content on mechanically-induced pod shatter and on header losses was studied. The pod suture compression method was simplest to perform and, with respect to crop moisture, gave results indicative of machine harvest shatter levels. Such a standardized mechanical shatter index may prove a useful criterion in soybean breeding selection for harvest shatter resistance.

A method of obtaining the standard error and some other moments for the ratios of biological measurements is given, with the conditions to be satisfied by the variables used to form such ratios. Some applications of the distributional properties of the ratios in the analysis of results from experiments are discussed.

An experiment was conducted in 1964 and 1965 to study the effects of hormone sprays on pod setting, pod filling and grain yield of black gram. Sprays of 2-naphthoxyacetic acid and p-chlorophenoxyacetic acid, alone and in 'mixture, and gibberellic acid and 1-naphthaleneacetic acid increased pod setting, but grain filling in pods and grain size were only slightly improved. 2-naphthoxyacetic acid gave the highest yield, followed by p-chlorophenoxyacetic acid, 1-naphthaleneacetic acid and a mixture of the first two, which increased yield by 56, 39, 36 and 35 per cent respectively over the control and gave economic returns.

A field experiment evaluating criteria for scheduling wheat irrigation was conducted from 1975 to 1977 in a sandy loam soil with treatments scheduled according to physiological stages, soil moisture conditions, pan evaporation and leaf water potential. Grain and straw yields, spikes/m, fertile spikelets/spike and number and weight of grains/spike were significantly influenced by treatments. Irrigation based on leaf water potential was as good as when based on physiological stages or soil moisture, and the use of pan evaporation was no better than other methods of scheduling.

This paper reports the heterotic pod production of three different crosses between a Nigerian local selection (N38) and three Trinidad Introductions (CF47, CF56 and CF207). The hybrids consistently outyielded the inbreds throughout the first 19 years of pod production. N38 × CF56 hybrid produced the highest number of pods per tree, closely followed by N38 × CF47 hybrid; while N38 × CF47 hybrid showed the best heterotic response. Pod production figures of (CD207)2 and (CD302)2, both double inbreds of N38, support the hypothesis that N38 is a Trinitario × local selection hybrid which segregate for pod production.