The present paper presents details of the population dynamics of Diabrotica v. virgifera LeConte beetles on six maize varieties of three different maturity classes, i.e. early (FAO 190), medium-early (FAO 250) and medium-late (FAO 280–300), grown in Central and Eastern Europe. The study was conducted in 2009/10 in the south-eastern part of Poland. The D. virgifera beetles were captured using two types of trap: pheromone (PTs) and floral-baited (FTs). Significant differences in beetle counts were found between: (i) the first and second year of the study (higher in 2009 than in 2010); (ii) the varieties of maize and their different growth stages; (iii) early and medium-late varieties of maize. Initially, depending on the availability of maize silk and pollen, the most numerous D. virgifera beetles were found on the early varieties followed by the medium-late varieties. The study also revealed a significant difference in the performance of the two types of trap used to monitor the number of adults, particularly during the initial period when arrival rates were high. Pheromone traps were more effective in catching D. virgifera beetles, especially during the flowering stage of maize. Floral-baited traps were most effective at the end of the active growth of maize, when the preferred food of D. virgifera was unavailable.

Three pastures, pangola–clover, setaria, and tropical grass–legume, were grazed for a 9-month period by 12 steers of initial live weight of 199 kg on each. For the first 5 months live-weight gains were, respectively, 1·2, 0·76 and 0·43 kg per day, mostly higher than could be expected for estimated dietary energy concentrations of 10·1, 8·9 and 8·7 MJ of metabolizable energy (ME) per kg of dry matter. The high live-weight gains were not explained satisfactorily by dry-matter intakes as measured from faeces voided and dietary digestible dry matter, but were possible if published values for the requirements of ME for growth and fattening were too high. Cell wall, in vitro digested cell wall and nitrogen in separated leaf and stem fractions were useful indices for evaluating pasture for grazing cattle, but they did not predict live-weight gain.

Bean cultivars Cargamanto (CIAT P590, indeterminate climbing, Type IV) and Puebla 152 (CIAT P498, indeterminate large vine, Type III) were grown at 20 and 60plants/m2 at two locations in Colombia; a cool, high rainfall, mountainous area (Popayan) and a hot, medium rainfall, valley (Palmira). The crop growth period was compressed and P590 failed to flower at Palmira.where plant shoot weights tended to be higher and root weights lower than at Popayan.

Midday soil temperatures at 10 cm averaged 7·8 °C lower and N2(C2H2) fixation rate and nodule fresh weight over ten-fold higher at Popayan than at Palmira. Increasing the plant population density increased yield but reduced seed weight per plant and the fresh weight of all other plant parts, with shoots more severely affected than roots. Density had little effect on carbohydrate concentration or N2(C2H2) fixation per plant. The cultivars accumulated carbohydrates in different amounts but had similar rates of N2(C2H2) fixation. Concentrations of ethanol insoluble carbohydrates were several times higher in all plant parts at Popayan. Soluble carbohydrates showed similar, but smaller, differences.

Male and female New Zealand White rabbits were exposed for 3h to 34 °C and 36 °C (both at 40% r.h.) when hydrated and dehydrated. Females had lower rectal and skin temperatures and respiratory rates than males (P < 0·001). Differences between the sexes in rectal temperature were greater at 36 °C than at 34 °C. Withholding water for 24h significantly increased the responses in rectal temperature; the differentials between hydrated and dehydrated males and females being 0·3 °C and 0·2 °C, respectively. In contrast, respiratory rates were lower in dehydrated than in hydrated rabbits, suggesting that the former were attempting water homeostatis at the expense of thermoregulation.

The results suggest that the performance of rabbits in the tropics is likely to be maximized when drinking water is available at all times, and that of males, particularly breeding bucks, might be improved simply by housing them in the coolest available location. Significant individual differences in observed responses point to the need for genetic studies of heat tolerance and the possibility of developing better adapted genotypes.

In a field experiment, the influence of different forms and methods of application of urea nitrogen on the rice rhizosphere soil nitrogenase was evaluated under simulated intermediate deep water situations. Nitrogenase was high when the soil received small amounts of nitrogen and phosphorus with a water level of 20–25 cm. Moreover, during and after the flash floods the nitrogenase activity was considerably increased. There was a significant reduction in the nitrogenase activity when the nitrogen was applied to the shallow water through urea briquettes, but when it was applied either behind the plough or between the rows, the activity was stimulated. Increased water level of about 50 cm for prolonged periods considerably reduced the nitrogenase activity. Results indicate that the method of application of urea nitrogen and the water level influenced the rhizosphere soil nitrogenase activity under intermediate deep water situations.

It has been shown in Part II that a glacial drift soil in a comparatively unweathered condition has a considerable power of absorption for ammonia, although it has sometimes been held that it is the weathered material in soils that is responsible for the absorptive power. Glacial drift, as exemplified in the Craibstone soil, however, though its weathering is geologically recent compared with that of many English soils, has been subjected to age-long weathering since the glacial period, and in the process of soil formation a certain amount of weathering with the resultant decomposition has necessarily taken place. Craibstone soil has also been shown (Table II, Part II) to contain a fairly large percentage of organic matter and it might be contended that the absorptive power was chiefly due to either or both of these factors.

The objective of the present study was to present the theory and application of best linear unbiased prediction (BLUP) in reciprocal recurrent selection (RRS). Seven progeny tests from two RRS programmes with popcorn (Zea mays L. ssp. mays [syn. Zea mays L. ssp. everta (Sturtev.) Zhuk.]) populations were conducted and analysed for expansion volume and grain yield. The interpopulation half- and full-sib family models were fitted using ASReml software. Half-sib selection is equivalent to selection for the general combining ability (GCA) of the common parents. With inbred full-sib progeny and BLUP analysis, it is possible to predict the general and specific combining ability effects. The standard error of prediction of the progeny effect was lower than the standard deviation of the best linear unbiased estimation (BLUE) estimate. For half- and full-sib RRS, the BLUE and BLUP provided highly correlated estimates of progeny genotypic values. The coincidence between selected parents ranged from 64 to 95%. With inbred full-sib progeny, the correlations between the BLUE of progeny genotypic values and the BLUP of GCA effects were lower. Consequently, the coincidence between selected parents was lower, ranging from 0 to 57%. The percentage of common selected inbred progeny based on the BLUE and BLUP of the progeny genotypic value ranged from 57 to 100%.

The following paper is the first of a projected series on the results of work which has been in progress in the Animal Calorimetry Department of this Institute during the past five years. Subsequent papers will deal with body temperature variations, effects of environmental temperature, metabolism, energy expenditure, etc.

The optimal feeding time of microencapsulated sodium butyrate (SB) in whole milk (WM) and starter feed on growth performance and health in dairy calves was evaluated. Forty-eight newborn Holstein calves (body weight (BW) = 39.45 ± 2.48 kg) were randomly assigned to one of the four treatment groups (12 calves per treatment; seven females and five males) in a complete randomized block design and fed (1) WM without microencapsulated SB (CON) supplementation; (2) 4 g/day SB added to WM since days 4–32 (SB-4-32); (3) 4 g/day SB added to WM since days 61–74 and an equal amount was added to starter since days 75–88 (SB-61-88) and (4) 4 g/day SB added to WM since days 4–74 and an equal amount was added to starter since days 75–88 (SB-4-88). Total dry matter intake, starter intake, BW, average daily gain and gain-to-feed were similar between treatments. Calves fed SB-4-32, and SB-4-88 had lower faecal score during pre-weaning, and overall. In addition, calves in SB-4-32 and SB-4-88 groups had fewer numbers of days with scours during the pre-weaning period, and throughout the study. Calves fed SB-61-88 had greater serum total protein during post-weaning. Post-weaning and overall albumin concentrations were greater in SB-4-32 and SB-4-88 calves and tended to be greater in the pre-weaning period compared to control calves. In general, the time of SB addition had no remarkable effect on performance but better faecal score within the pre- and post-weaning periods.

This study was carried out to determine the effects of different irrigation levels and different tillage and sowing methods on the amount of irrigation water, evapotranspiration, water productivity (WP) and yield in the second crop soybean in Çukurova Region, Turkey. Three irrigation levels were applied (I100: completion to the field capacity of the available water of 60 cm soil depth weekly. I70: 70% of the water applied to I100, I50: 50% of the water applied to I100), five tillage and sowing methods were used (T1: traditional soil tillage, T2: reduced soil tillage, T3: reduced soil tillage, T4: ridge tillage, T5: no-tillage). The research was carried out in a randomized block split-plot design with three replications. The result of, the highest yield was obtained in I100xT1 with 4990 kg/ha, while the lowest yield was obtained in I50xT3 with 3150 kg/ha in irrigation x tillage interactions. When the water consumption values of plants were analysed, the highest was obtained with 632 mm I100 and the lowest with 399 mm I50. When WP values were analysed, the highest was obtained with 8.7 in I50 and the lowest in 6.6 and I100. As a result, full irrigation and direct sowing methods (I100T1) are recommended in soybean cultivation considering the highest water-yield relationship in the Mediterranean Region.

With the great increase in the use of palm kernel cake, which has taken place in this country in the last few years, attention has been drawn to the rancidity which the cake is liable to develop under certain conditions. R. B. Calder (see this Journal, April, 1916, VII, 470) has shown that the cake develops rancidity under sterile conditions and concludes that the action is due to the presence of a lipase. Calder has taken as his criteria of rancidity a sour smell in some cases and an acid reaction with litmus in others. There is some confusion in the use of the terms “rancidity” and “ acidity.” Although rancidity stands in close relationship to acidity and invariably accompanies a high acidity in oils and oil cakes, the terms are not synonymous.

1. A cross-bred sheep was fed successively with supplements of dried skim-milk or lactose. The effect of the supplements on the lactase activity of the rumen liquid was followed.

2. Lactase activity was expressed as mg. lactose hydrolysed per ml. rumen liquid, or per mg. protein nitrogen. The enzymic activity fluctuated considerably after a change in the diet, and did not become constant even when the ration remained the same for 7 weeks.

This group, which is concerned with the applications of mathematics to agricultural science, is sponsored by the Agricultural and Food Research Council. It was formed in 1970, and has since met at approximately yearly intervals in London for one-day meetings. The twenty-third meeting of the group, chaired by P. H. Nye of the Department of Plant Sciences at the University of Oxford, was held in the Wellcome Meeting Room at the Royal Society, 6 Carlton House Terrace, London on Friday, 7 May 1993, when the following papers were read.

A central issue in the husbandry of seed crops of perennial tropical grasses is the disposal of residues from previous crops. Flowering of these grasses is usually poorly synchronized, and the sudden removal of all shoot material by burning, mechanical removal or stock concentration is necessary to create a population of tillers of similar age (Humphreys & Riveros, 1986). There has been little critical study of alternative systems of residue disposal and their effects on the ways in which seed yield is realized. Questions requiring attention are whether cutting differs from burning in its effects, and whether the fuel load, determined by the size of the previous crop, influences the potentially damaging effect of fire on crown buds.

Analysis of 21 years' cotton yield data from factorial experiments at three sites in the Sudan Gezira established that yields were significantly increased by nitrogenous fertilizer, that close spacing outyielded wide spacing and that variety X1730A (L type) outyielded variety MSDS (a Sakel type). The effect of nitrogen varied depending on variety and spacing and there were also marked variations from year to year in the effects of nitrogen, spacing, variety and some of the interactions. Year-to-year variations in the overall level of yield were very pronounced and accounted for more than half of the total variance at each site. Causes of year to year variation and the mechanism of the treatmenteffects will be discussed in subsequent papers.

An experiment to study the effect of row direction on the light interception, growth and yield of three wheat cultivars sown at three different dates was conducted at Punjab Agricultural University, Ludhiana during rabi seasons 1982–3 and 1983–4. The results showed that sowing in a north-south direction resulted in 0·20 and 0·22 t/ha higher yield than sowing east-west. Bi-directional sowing gave further increases of 0·30 and 0·18 t/ha over north-south direction during 1982–3 and 1983–4 respectively. Late sowing significantly reduced yield.

Copy number variation (CNV) is a very common type of gene variation with high frequency. In recent years, CNV has been paid more attention in various fields, especially in livestock and poultry breeding, which has promoted the progress of breeding. WW domain binding protein 1-like (WBP1L) is a protein coding gene, which plays an important role in cattle populations, and its function has been extensively studied, but it is not clear whether the copy number of the gene can affect the growth and development of cattle populations. In this study, CNV of WBP1L gene was detected in 732 cattle of seven breeds (Qinchuan cattle, QC; Pinan cattle, PN; Yuengling cattle, YL; Xianan cattle, XN; Jiaxian cattle, JX; natural Guyuan cattle, NGY; Jian cattle, JA). In addition, the relationship between CNV and growth phenotype of cattle was studied. The experimental data indicate that the copy number of WBP1L was obviously correlated with heart girth of PN cattle (**P < 0.01), rump length (RL) and body weight (BW) of PN cattle (*P < 0.05), withers height (WH), RL, body length, chest depth and BW of JX cattle (*P < 0.05), WH of NGY cattle (*P < 0.05) and WH of JA cattle (*P < 0.05). It was proved that CNV of WBP1L gene could be used as molecular marker locus for genetic breeding of the above four cattle breeds.

Field experiments, conducted on alluvial soil of Jalandhar during 1984–5 and 1985–6 with four rates of application each of N, P and K and four potato cultivars, Badshah, Bahar, Lalima and Jyoti, revealed significant responses to N and K. Badshah, Bahar and Lalima responded to 240 kg N/ha while Jyoti responded to 160 kg N/ha. Badshah did not respond to K. Bahar responded to 150 K/ha whereas both Jyoti and Lalima responded to 50 kg K/ha. Varietal responses to N were related to yield and crop duration while the responses to K were related to K composition of tubers. N showed inconsistent effect on percentage dry matter of tubers, but K decreased it. N increased concentration of N and P but decreased that of K.

The intensive finishing of steers on simple rations of 10% sorghum stubble and 90% sorghum grain plus urea was investigated. Fine grinding of the grain resulted in a lower mean daily intake, but a significantly greater efficiency of conversion of feed to carcass weight gain (P < 0·01) than coarse grinding the grain. Coarse chaffing of the stubble significantly reduced the intake of the stubble in comparison with hammer milling, but had no significant effect on rate of body weight gain, total feed intake or efficiency of feed conversion.

The addition to the ration of either 1 mg of selenium, or 200 mg vitamin E, 200 mg vitamin E and 100 mg vitamin K per day had no significant effect on rate or efficiency of body or carcass weight gain. Seven out of 32 steers which were not injected with 3 million i.u. of vitamin A at the start of the experiment exhibited nyctalopia. None of the 32 steers which received the vitamin A injection had hepatic vitamin A concentrations less than 33 μg/g. Vitamin A injection did not have a significant effect on the rate of body weight gain (mean ±S.E. 1·3 ± 0·03 kg per day), efficiency of feed conversion (10·4 ± 0·16 kg D.M. per kg carcass weight gain), or time to attain slaughter weight (133 ± 3 days). Drenching twice with thiabendazole had no significant effect on rate of body weight gain.