The study of two years' hay crops indicates that the composition of the hay steadily changes throughout the period commonly covered by the hay-making season.

The nature of the change depends to some extent upon the character of the season. In the summer of 1909 when the climatic conditions favoured steady growth there was a steady production of protein and fibre and a considerable assimilation of ash ingredients, notably silica. In the following summer the effects of a severe climatic set-back in the later part of June was seen in an almost complete suspension of growth, and notably in the production of protein.

In both seasons there was a steady fall all round in the digestibility of the hay, which in the end more than counterbalanced the increase in weight of the crop.

In both seasons the best results were obtained by cutting about the beginning of July. A fair amount of latitude in the time of cutting —say, a week or 10 days—may be allowed, however, without very seriously impairing the nutritive value of the crop. There was evidence, nevertheless, in each year of appreciable deterioration after the middle of July.

Several plants are cultivated for medicinal and aromatic purposes. Foxglove (Digitalis lanata) has been introduced into India from Western Europe and is cultivated for medicinal use. The leaves of D. lanata contain various glycosides, namely digoxin, gitoxin and gitalin, which are of medicinal value. This crop is cultivated throughout the year but not much information is available about

seasonal influence on the glycoside content. Hence, attempts are made to assess the effect of seasonal variation on total glycoside content and to arrive at an optimum season for harvesting the crop.

It was demonstrated that abiotic chemical precipitation could account for a major proportion of iron hydroxide deposition in drainage water. In filter-sterilized (0·22 μm) drainage water samples from ochreous sites 84% of the total iron in solution was precipitated within 48 h. It was also shown that ferric hydroxide precipitates could catalyse the precipitation of ferric hydroxides in drainage water exposed to the atmosphere.

Reproductive performance has been reported to be declining within the UK dairy herd due to continued selection for increased milk production. The aim of the current work was to assess the influence of genetic merit for milk production (as described by PIN95, the index in use at the time), and level of herd performance on reproductive performance. Fertility records from seven commercial dairy farms over a two-and-a-half year period between August 1997 and January 2000, providing a total of 1003 cow records (with a mean genetic merit of 38·6 (±0·80) PIN95) were collected. The influence of genetic merit for milk production, herd mean 305-day milk yield and their interaction on the reproductive performance of individual dairy cattle was estimated. Additionally, 90-day milk yield, 90-day body condition score and deviation from herd mean 305-day milk yield were also investigated for their influence on fertility. A series of regression models using the Proc GLM procedure in SAS were run using data from those cows that conceived during the monitoring period (n=874) (PIN95=38·8±0·83). The models included the variables, year of calving, month of calving and parity. The results showed that days from calving to conception and services per conception increased significantly both with herd 305-day milk yield, and within herds with deviation from herd 305-day milk yield level. Calving to conception also increased with reduced body condition score of cows at 90 days postpartum. Genetic merit (PIN95) was not significantly related to these fertility measurements.

Forty-five normal lactating buffaloes from Punjab Agricultural University, Dairy Farm herd, were used for this study and were divided into three groups as group I (control), group II (showers) and group III (wallowing). The study was conducted from May to September in two periods, May–June as period I (hot and dry) and July–September as period II (hot and humid). Potassium concentration was estimated on a flame photometer. The overall average values (m-equiv/l) were found to be lowest in the control group (21·5 ± 1·27) and highest in wallowing (24·3 ± 1·20). Lower values were obtained in period I than in period II. Different correlations of potassium concentration in red blood corpuscles with climatic variables are discussed. Erythrocyte potassium concentration may act as an index of heat tolerance in buffaloes.

Initial pH of buffalo semen as measured electrometrically is 7.2 ± 0.025 and the buffering capacity 1.40 ± 0.026. Sulphamezathine in glucose–egg yolk–bicarbonate diluent depressed fructolysis in buffalo semen. This depression is considered to be a factor in the better maintenance of motility in this than in other media investigated. The more alkaline pH of this medium also appears to be beneficial in preserving motility on storage.

In laboratory studies, the amount of N mineralized under waterlogged conditions during 14 days at 30°C was significantly correlated (P < 0·001) with the activities of amidase, glutaminase and asparaginase in soil when these enzymes were assayed by either a nonbuffer or a buffer method using appropriate substrates. N mineralization under waterlogged conditions was also significantly positively correlated with N mineralization under aerobic conditions, especially at 25 and 35 °C (P < 0·001). Generally, the results indicate that the use of amidase, glutaminase and asparaginase activities in predicting plant-available N in soils deserves more attention.

T-trellis apple trees treated with combinations of fungicides and insecticides applied with a boom sprayer had a lower percentage of fruit damage from diseases and insects than those treated with an airblast sprayer. With the boom sprayer, chemical deposit was uniform in distribution between outer and inner parts of the tree canopy, but with the airblast sprayer there was more than a threefold difference in deposit between parts of the canopy. The boom sprayer was inferior to the airblast sprayer in the control of apple aphids (Aphis pomi) when vertical top growth (watersprouts) had grown to 0·7–1 m. Management of aphids with a boom sprayer would probably require the control or periodic removal of watersprout growth, or the use of systemic insecticides.

Three composite populations of oats were grown at contrasting sites in the north, east and west of Scotland for four successive generations from F3 to F6. Analyses of variance and canonical analysis both showed that the genetic constitution of the composites was responsible for a greater proportion of the variation than locations (sites). This suggests that either natural selection was not operating to any great extent or the effect of natural selection was very similar at the three sites. These findings were supported when selections were taken from one of the populations and subjected to canonical analysis. The implications for oat breeding in Scotland are discussed.

A key need of the global change research community is to be able to synthesize the data collected by scientists from a wide range of disciplines and use it to make predictions about our future environment. In an agricultural and forestry context, this will allow predictions of yields under elevated atmospheric CO2 levels and/or changed climate using data from studies of both the direct effects of global change on plant growth and physiology and indirect effects on soil fertility, water resources, pests and diseases.

A conference held at the University of Reading, UK in September 1999, and organized under the auspices of Focus 3 (Global Change Impact on Agriculture, Forestry and Soils; http://mwnta.nmw.ac.uk/GCTEFocus3) of the IGBP Core Project “Global Change and Terrestrial Ecosystems” addressed many of these issues.

1. The effect of feeding three levels of concentrates on the organic matter digestibility of two kinds of herbage was determined in four Latin square trials with four wether sheep.

2. Analysis of variance of the trials showed that the organic matter digestibility of all mixed feeds was significantly higher than that of the corresponding herbage. With one exception, the organic matter digestibility of the mixed feeds within each trial was not significantly different.

3. The digestibility coefficients of the concentrates, derived by difference, were invariably high and exceeded 100% for four levels of addition. This indicated a marked improvement of the digestibility of herbage when it was fed with certain levels of concentrate.

4. A possible explanation of the increase of digestibility was discussed and the practical implications of the results indicated.

Results of our previous work were published in the Journ. of Agric. Sri., IV, 1911. There, also, a brief summary of the chief papers published on the subject of the fat globules was given, to which it is unnecessary to refer in detail here.

When the work was first commenced in 1909, the problem before us was the consideration of the variation in the size of the fat globules, with relation to churning, as regards the different breeds of cattle. The breed was considered because it was usually supposed that this was one of the chief factors which influenced churning. The most definite result of our work was that it was shown that consideration must be given to the character of the milk, irrespective of the breed. This conclusion is quite contrary to that of other workers, but an examination of their figures shows, undoubtedly, that this is actually the case: the results given by Woll (Digestion Expts., Seventh Annual Report, Agric. Expt. Stat, Wisconsin, 1890, 238; also Agric. Sci., 1892, vi, 445) emphasise this point particularly. It is also shown by this year's work, as may be seen from Tables V–XI.

The comparative size of the globules has been worked out very thoroughly by Gutzeit, who measured the mean volume of the globule. Other workers give their results as “relative sizes.” In our work we attempted to ascertain the distribution of the fat in the globules, and to this end the number of globules of each size was determined, and curves were drawn. The result of this, however, was negative. At that time we were considering the breeds of the cows from which the milks were obtained; had we considered them solely as milks of a certain mean size of globule, much more might have been achieved.

An apparatus was devised to give an absolute figure for the churnability of any cream, but, until the effect of the other factors has been determined, it is impossible to interpret the results. Some experiments to ascertain the optimum temperature were described also.

1. Early transplanting of seedlings resulted in the production of rice plants with greater total tiller and leaf number, greater total leaf area, leaf area per shoot and per leaf lamina, greater height, greater total fresh weight yield and yield of grain than late transplanting.

2. Early transplanting reduced the number of days from seeding to ear emergence.

3. Deep transplanting favoured greater leaf area per shoot and per leaf lamina and greater maximum tiller number and reduced the percentage tiller mortality.

4. Deep placement of fertilizer resulted in the production of plants with greater tiller and total leaf numbers, greater height, greater total leaf area, leaf area per shoot and per leaf lamina and greater total fresh weight and grain dry weight than surface placement.

5. Deep placement of fertilizer hastened the time of ear emergence of late transplanted seedlings.

6. The practical significance of these findings is that early transplanting of seedlings (30 days old), shallow transplanting, and deep placement of fertilizer will lead to greater yield of the rice variety BG 79.

In the course of an investigation on the nitrification process in soils a series of pot experiments was set up to compare the manurial actions of some typical organic nitrogen compounds. The laboratory work was interrupted at an early stage; the results of the pot experiments are briefly described in this note.

Thin-layer chromatography and infra-red spectrosoopy were used to identify the components of technical Thanite. A method is developed for qualitative and quantitative determination using a gas liquid chromatograph (GLC) equipped with a flame ionization detector. Two major peaks, having retention times 1 and 5 min, were obtained. This was achieved using a glass column (15 × 0·3 cm), packed with diethylene glycol (1·5%) on chromosorb W, 60–80 mesh, at temperature range 70–170 °C. The results obtained by GLC showed that 33·7–55·8%, and 36·6–68·3% of the initial deposit of Thanite on cotton leaves degraded within 12 h from exposure to sunlight and ultraviolet irradiation respectively. One fifth of the initial deposit of Thanite on cotton leaves was lost after 24 h from spraying, then 70 % of the compound was dissipated after 3 days. Incubation of Thanite with rumen liquor at 39 °C for 24 h under anaerobic conditions resulted in degradation of 45–74% of the initial concentration.

The oat kernel, caryopsis or groat, is generally covered with fine silky hairs termed trichomes. The trichomes of naked oat are partly lost during threshing and handling of grains when the lemma and palea are removed and the surface of the grain is exposed. Trichomes can cause itchiness and more serious reactions in those handling the grains. Trichomes also accumulate and form fine dust and can block up machinery. Trichomes are clearly problematic and growers of naked oat are eager to have oat cultivars with reduced numbers of trichomes. Experiments compared the differences in trichome numbers of naked-oat cultivars and threshing settings. The cultivars differed considerably in pubescence. Cultivars Lisbeth and NK 00117 had most trichomes and cv. Bullion the fewest. Completely bare or polished grains were not observed. Pubescence was not associated with grain weight or test weight. However, grains from the lowermost spikelets of the panicle had fewer trichomes than those from the uppermost spikelets. For cv. Bullion, some threshing settings, including increased cylinder speed, slightly increased grain polishing such that grains had some areas completely free of trichomes. Reduction of the concave clearance in the combine harvester had a similar effect. However, threshing settings did not affect the trichomes of cv. Lisbeth. Adjusting threshing machinery settings was generally not an efficient means of solving the problems associated with naked-oat trichomes, but cultivar differences existed and further efforts in breeding to reduce trichome numbers are required.

Experiments were conducted in association with farmers during 1977, 1978 and 1979 on a River Estate sandy loam at Valsayn and on a Cunupia clay loam at Piarco, Trinidad, to assess the relative importance of components in a set of practices for wetseason production of ‘yellow shell’ pods of ‘blackeye’ type of cow pea (Vigna unguiculata (L.) Walp.). Though the response of the cow pea growth, yield and seed quality characteristics were similar at both locations, crop performance was consistently better at Valsayn and was attributed to more favourable soil conditions and to a lower incidence of pests (mainly Ceratoma beetles), cow pea severe mosaic virus, and weeds. Overall, it was found that pest control was the most important management factor, accounting for a mean yield increase of 144%. The adoption of the improved cultivar, California Blackeye No. 5, increased yield by 77%. Other inputs resulting in significant yield increases were, in order of magnitude, weed control (40%), roguing of mosaic infected plants (37%) and high plant density of 110000 plants/ha (23%). A fertilizer treatment did not significantly increase yield. The results suggest that adoption of the insect control treatment by farmers in their cultivation of an improved cultivar sown at high plant density, the use of herbicide and roguing of mosaic infected plants have practical potential and would be economically justified for the production of high yields and good quality ‘yellow shell’ pods of vegetable cow pea for processing.

A suitable modification of the microbiological method for assaying pantothenic acid was developed and the pantothenic acid content in various kinds of poultry-feeding stuffs determined by its use. To assure quantitative liberation of the total amount of the pantothenic acid from the samples it is recommended to digest the samples first with Clarase.

Pantothenic acid content was determined in poultry feeds of animal origin, such as fish-meal, meat-scrap, liver-meal and different kinds of milk-powder. It is remarkable that different kinds of fish-meal differ markedly in their pantothenic acid content.