Total Dry Matter Content Research Articles

Incidence, appearance and development of potato mop-top furovirus-induced spraing in potato cultivars and the influence on yield, distribution in Denmark and detection of the virus in tubers by ELISA

23 potato cultivars were grown in fields infested with potato mop-top virus and spraing was assessed on tubers at harvest and after storage. Large differences in spraing susceptibility were found between cultivars. Compared with other countries, spraing in Denmark is characterised by a high incidence at harvest, a low increase during storage and a very low proportion of superficial spraing. Decrease in spraing during storage was recorded in two cultivars. DASELISA tests for PMTV in tubers revealted a high reliability. Mapping of PMTV in important Danish potato growing areas showed that the virus is widespread. Occurrence of spraing did not influence total yield or dry matter content. Soil acidity did not influence incidence of spraing but it was more common on coarse-grained soil than on finer sandy soils. PMTV in viruliferous resting spores ofSpongospora subterranea was inactivated by heating to 90°C for 15 minutes.

Growth Response of White Prawn, Penaeus indicus, to Dietary L-Carnitine

Juveniles of Penaeus indicus were fed a biosynthetic product, L-camitine, at concentrations of 100 ppm (Tl), 250 ppm (T2), 500 ppm (T3), 750 ppm (T4) and 1,000 ppm (TS) in a fish meal-based supplementary feed having 40% protein. A diet without L-camitine supplement served as control (TO). The growth study was conducted for 120 d in nylon hapas, arranged in a brackishwater pond. AH diets with L-camitine produced significantly higher growth than the control (P<O.Ol). The diet containing 500 ppm camitine promoted maximum growth (14.82 ± 2.86 g) compared with the control (9.07 ± I.67 g). Feed conversion efficiency, assimilation efficiency and protein efficiency ratio were high in carnitine-fed prawns; optimum values were recorded for the 500 ppm treatment. Digestive enzyme (amylase, protease and lipase) activities were high in the mid-gut of prawns fed carnitine diets. RNNDNA ratios in the muscle and hepatopancreas of prawns under carnitine treatments were higher than the control. Total dry matter and protein contents of the body increased in prawns fed L-camitine. Lipid content decreased in all carnitine-fed groups with maximum value in the control (2.69%), indicating enhanced lipid catabolism, thereby sparing energy and protein for growth and anabolic processes.

The effects of particle size, connective tissue and cooking regime upon properties of washed mechanically recovered broiler meat

Mechanically recovered meat (MRM) from broilers was washed with water, with or without prior chopping and with or without sieving to remove connective tissue. The resultant protein extract was mixed with salt and cooked in a one‐step (directly to 80°C) or two‐step (to 55°C and then to 80°C) cooking regime, to form gels. Washing broiler MRM gave stronger gels with lower cooking loss and expressible moisture than unwashed broiler MRM. These washed gels were also lighter in colour and less red. The best products were produced when some of the collagen had been removed by sieving, but not if the samples had Wrst been chopped, even though the total protein and dry matter contents were also reduced. A two‐step cooking procedure enhanced gel strength. Evidence of a more porous, but dense, structure of washed broiler MRM subjected to a two‐step cooking treatment was given by scanning electron microscopy and these differences could be related to the changes in gel strength and water holding.

Growth, yield and nutrient uptake of taro grown under upland conditions

Abstract There is a scarcity of basic information on dry matter accumulation by various plant organs, nutrient uptake, and yield of taro [Colocasia esculenta (L.) Schott] grown under upland conditions. These data are essential for the development of technological packages, growth simulation models, and decision support systems designed to promote agrotechnology transfer of the crop in the tropics. Two taro cultivars were planted and harvested for biomass about every six weeks during the growing season. At each harvest, plants were separated into various plant parts and their dry matter and nutrient content were determined. There were no significant differences (P<0.05) in total and edible dry matter content between cultivars. However, cultivar ‘Lila’ absorbed significantly smaller amounts of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and zinc (Zn) than cultivar ‘Blanca’, suggesting that it had a higher nutrient‐use efficiency. Fresh corm yields were not significantly different and averaged 20,221 kg/ha for both cultivars.

Assessment of five cultivars of potato (Solatium tuberosum L.) in a competition diallel

SummaryIn 1992 and 1993, potato cultivars Cara, Estima, Pentland Dell, Pentland Javelin and Torridon were assessed in all possible pairings in three consecutive drills, such that one member of the pair (the cultivar) was the centre‐drill, and the other member (the neighbour) was in the two adjacent drills. Each year the trial was a randomised complete block design with four replicates. Inter‐cultivar competition was present for height, total tuber yield, ware yield and dry matter content, but not for emergence and maturity. Cultivar heights and dry matter contents under inter‐cultivar competition and in pure‐stands were highly correlated, whereas for total and ware yields, the rankings of cultivars in pure‐stands were different from those under competition.Pure‐stand yields were predicted for the two years separately because of year × cultivar and year × neighbour interactions. When the average total yield of the outer‐drills was used as a covariate to adjust centre‐drill yields to pure‐stands, predicted yields were closer to those observed than were yields under competition, but there was little improvement in the correlations. In contrast, not only were the predicted values even closer to the observed ones when based on individual neighbour effects, the correlations were much higher (r = 0.76–0.94). Unfortunately, in plant breeding trials with large numbers of entries, precise estimation of individual neighbour effects would require an unrealistically large number of replicates. Hence, for the final stages of yield assessment of new cultivars, it is still desirable to use multiple‐drill plots and to discard the outside drills where inter‐cultivar competition can occur.

Accumulation and Partitioning of Dry Matter in Water Yam

AbstractThere is a scarcity of field‐growth data from which a yam (Dioscorea alata L.) growth model could be developed to promote agrotechnology transfer of the crop in the tropics. A 2‐yr field study was conducted on Corozal soil (clayey mixed isohyperthermic Aquic Tropudults) in an initial effort to collect data on patterns of leaf area development and dry matter accumulation and partitioning among various plant parts during growth and development of yam plants. In the first year of the study, plants of D. alata cv. Gunung were subjected to fertilizer rates of 0, 667, 1333, 2000, and 2667 kg ha−1 of a 15‐2.2‐12.4‐3% (N‐P‐K‐Mg) commercial mixture at 5O d after planting (DAP). Biomass harvests were conducted at 60, 90, 120, 150, 180, and 210 DAP. For all plant parts studied, dry matter content was not significantly affected by fertilizer treatment. Even after excluding application of fertilizer during the second year, there were no statistical differences in total and tuber dry matter content between years. Maximum leaf area index values (LAI ≈ 8) were attained by 140 DAP. During this period, leaves and vines accounted for at least 80% of the total plant dry matter; thereafter, their dry matter content declined. After 140 DAP, increases in total dry matter were the result of rapid increases in tuber dry matter accumulation. The lack of response to fertilizer treatment and high tuber dry matter production suggest that the preplanting soil nutrient status was adequate to support optimum growth of the yam cultivar used during both years of this study, even without the application of fertilizer.

Crecimiento, extracción de nutrimentos y rendimiento de yautía (Xanthosoma spp.) producida bajo condiciones semiáridas

Hay muy poca información sobre los requisitos de riego para yautía producida en zonas semiáridas. Se hizo un estudio para determinar el crecimiento, la extracción del suelo de varios nutrimentos y el rendimiento de yautía irrigada con cantidades de agua equivalentes a fracciones de la evapotranspiracion. Los tratamientos de riego se basaron en coeficientes de evapotranspiración (medidos con un evaporímetro clase A) que fluctuaron desde 0.33 hasta 1.32 con incrementos de 0.33. Se sembraron plantas de yautía en el campo y se cosecharon aproximadamente cada 6 semanas. En cada cosecha se determinó la acumulación de materia seca en varios órganos de las plantas, la extracción de N, P, K, Ca, Mg y Zn y el rendimiento comercial de cormelos. Durante los primeros 278 días después de la siembra, las plantas regadas con el 99 y el 132% del agua evapotranspirada (AE) exhibieron contenidos totales de materia seca similares; sin embargo el contenido de materia seca en éstas fue significativamente mayor que en plantas que recibieron 33 y 66% de AE. La extracción de N, P, K, Ca, Mg y Zn en plantas que recibieron el 99 y el 132% del AE fue similar; por otro lado el contenido de estos nutrimentos en plantas que recibieron el 33 y el 66% del AE fue considerablemente menor. El rendimiento de plantas que recibieron el 99% del AE fue mayor que el de las plantas que recibieron 33 y 66% AE, pero significativamente menor que el obtenido en plantas irrigadas con el 132% del AE. El rendimiento comercial más alto, 19,479 kg/ha, se obtuvo en plantas irrigadas con el 132% del AE.

Effect of Defoliation and Deflowering on Post‐Flowering Dry Matter Distribution in Chickpea (Cicer arietinum L)

AbstractStudies on source‐sink relationship were conducted in two chickpea varieties Cicer arietinum L. namely, Kabuli (L‐550) and Desi (BG‐256). The primary objective of the present study was to assess the influence of source/sink manipulation by defoliation or deflowering or both on dry matter accumulation in different vegetative parts. Seeds were sown in earthen pots containing sandy loam soils. Plants were raised under normal moisture conditions following recommended agronomic practices. In defoliation treatment all the freshly formed leaves were removed from the onset of flowering until harvest. The leaves formed earlier were kept intact. Removal of flower buds from start of flowering until harvest contributed deflowering treatment. Defoliation and deflowering treatment is a combination of both, whereas untreated plants served as control. Significant differences in dry matter distribution and total soluble sugar (TSS) content as a function of source sink manipulation were observed between the varieties. Defoliation treatment preferentially increased more stem dry weight (DW) in L‐550 and more root and nodule dry weight in BG‐256. In both the varieties deflowering treatment resulted in increased leaf and stem DW. This treatment also resulted in increased root and nodule DW in BG‐256, but only nodule DW in L‐550. When defoliation treatment was combined with deflowering, in both the varieties a decrease in DW in leaf and stem and an increase in DW of root and nodule were observed. Total dry matter content increased 2–3‐fold with deflowering in L‐550 but in Bg‐356 there was no significant increase, indicating a possible role of flowers and reproductive organs in dry matter accumulation. Similar results were obtained even with defoliation, which indicates the major role played by leaves formed before flowering in L‐550, and leaves formed after flowering in BG‐256. Thus, this study suggests variation in the functional role of leaves formed before and after flowering.

Partitioning of Dry Matter in Tanier (Xanthosoma spp.) Irrigated with Fractions of Evapotranspiration

The accumulation and partitioning of dry matter was determined in tanier plants irrigated with fractions of the water lost through evapotranspiration (WLET) in an effort to establish growth analysis data from which a tanier growth (simulation model could be developed. The irrigation regimes were based on Class A pan factors ranging from 0·33 to 1·32 with increments of 0·33. Tanier plants were planted in the field and harvested for biomass production about every 6 weeks during the growing season. At each harvest, plants were separated into various plant parts, and their dry matter content was determined. The first 90 d after planting (DAP) were characterized by low rates of dry matter accumulation, with only leaves and petioles showing substantial growth. A grand growth period followed in which leaves, petioles, and roots rapidly accumulated dry matter until 278 DAP. During this period, plants that received 0·99 and 1·32 WLET exhibited similar total dry matter content, and this was significantly greater than in plants supplied with 0·33 and 0·66 WLET. Cormel dry matter content peaked at 29% of total plant dry matter by 322 DAP in plants replenished with 1·32 WLET. Partitioning of dry matter to cormels in other treatments was significantly reduced. Partitioning of dry matter to corms increased linearly throughout the growing season in all treatments. Dry matter partitioning to suckers and the number of suckers formed from plants replenished with 0·33 and 0·66 WLET was greater than in the more irrigated treatments.

Effects of Winter Cover on Yield Components of ‘Elsanta’ Strawberries

Abstract In three experiments, yield components of the summer-planted strawberry cultivar ‘Elsanta’ under fibre-cloth winter cover (October-April) as well as on plastic covered raised beds were studied. All winters were mild, and winter frost damage did not occur. In one experiment, fibre-cloth covered plants developed more leaves during the autumn and more flowers the following spring. Fibre-cloth increased total yields by about 25% in two out of three experiments. In two experiments, fruit size increased as an effect of fibre-cloth cover. Ripening was accelerated in all three experiments. The overall effect of dark plastic on raised beds was small, increasing total yield in only one year. In a few cases total and soluble dry matter contents of fruits were sligthly increased by fibre-cloth cover or dark plastic on raised beds.

Response of No-Till Corn to Nitrogen Source, Rate, and Time of Application

A 3-yr N-source study was conducted on a site where urea was known to be less effective than NH4NO3 (AN) for no-till corn (Zea mays L.) production. The purpose of the study was to compare two urea-containing N sources thought to have lower N loss potential than AN and urea at two rates and times of application. Sources evaluated were urea, AN, Tennessee Valley Authority (TVA) experimental urea nitric phosphate (UNP) and TVA experimental urea ammonium phosphate (UAP). The soil was a Pope (coarse-loamy, mixed, mesic Fluventic Dystrochrept), which is an acid soil with a C.E.C. of 12.1 cmol/kg and organic matter content of 3.7%. Nitrogen rates of 80 and 160 lb/acre were broadcast either at planting or 4 to 5 wk after planting. Experimental design was a randomized block with three replications. Results showed that AN and the TVA experimental materials performed comparably and that both were better than urea in grain yield and N content of total dry matter. Urea performed as well as the other sources in total dry matter accumulation. Delayed application of N increased grain yields from all N sources when compared with application at planting.

Effects of Simulated Hail Damage on the Yield of Forage Maize

Hail damage was simulated with defoliation, leaf tearing and damage to ears and stems, applied at five stages and three levels of intensity on forage maize grown in Belgium. Leaf tearing alone had little effect on total dry matter yield. Decrease of yield was the highest when treatments were applied around tasseling-anthesis. Effects on total dry matter content were small.

Plant traits and yield stability of dry bean (Phaseolus vulgaris) cultivars under drought stress

SUMMARYThe objective of this study was to identify traits related to growth and yield response under drought stress in the field which would show less variation than yield itself. Experiments were conducted in 1987, at Durango, Mexico and at Michigan, USA. Twenty-six dry bean genotypes were sown under supplementary irrigation and terminal drought stress. Plant samples were taken at 50% flowering, mid-pod-filling and physiological maturity. At both sites, leaf expansion rate and crop growth rate at mid-pod-filling were greatly reduced by drought stress, resulting in significant reductions in total dry matter (DM) above ground and seed yield at physiological maturity. Because of differences in the timing and intensity of the drought stress, the yield components were affected differently at each location. Total DM content at physiological maturity, harvest index and number of pods/m2 were the only traits positively correlated with yield under stress at both locations. In order to evaluate a group of genotypes for adaptation to drought on the basis of seed yield, the genotypes should be grouped according to their phenological characteristics to stress them evenly.

Free Amino Compound Total Nitrogen and Dry Matter Content of Summer Potatoes During Growth in Southern Ontario

The free amino compound profiles, total nitrogen and dry matter content of tubers from five summer potato cultivars grown at Harrow and Simcoe, Ontario were monitored for four weeks commencing 3 July, about 80 days after planting in an attempt to determine the contribution of these factors to differences and changes in chipping performance which could not be accounted for by tuber sugar levels. In general: 1) tubers of the best chipping cultivars contained more dry matter and less amino compounds and total nitrogen than the poorer chipping cultivars at each harvest; 2) growth location differences were noted for corresponding cultivars and harvests; 3) larger proportions of the more intense Maillard colour forming amino compounds were found in tubers of the poorer chipping cultivars; and 4) tuber amino compound and total nitrogen levels decreased, and dry matter contents increased over the harvest period. Thus, the level and distribution of amino acids and the total nitrogen and dry matter content of tubers may be important factors contributing to the intensity of chip colour.

Dry matter content in silage maize; assessment of the role of growth and water loss

Effects on total dry matter content (MSt) due to a given amount of growth or water loss by plant parts are predicted. Analysis of experimental data show a decreased contribution of ear growth and an increased contribution of water loss by the stover, as ripening proceeds. Beyond 25% dry matter content, the major part of MSt increase was due to loss of water by the stover

Partitioning of carbon, nitrogen, phosphorus, potassium, calcium, and magnesium in a semidwarf high-yielding rice variety: comparison with a conventional japonica variety

To clarify the physiological character of the high-yielding rice (Oryza sativa L.) varieties, dry matter production and partitioning of C, N, P, K, Ca, and Mg were compared between Suweon 258, a semidwarf indica variety and Musashikogane, a conventional japonica variety under pot conditions. Translocation of C and N in plants was investigated using tracers, 13C and 15N, respectively. The total dry matter and carbon content were similar in the two varieties. However, the panicle weight of Suweon 258 was 23% larger than that of Musashikogane due to the higher weight ratio of panicle/shoot. The Suweon 258 plants actively stored and exported carbohydrates in the culm plus leaf sheath, and also showed a higher partitioning of C, N, P, and Mg to the panicle, whereas the percentage distribution of K. and Ca to the panicle was similar in the two varieties. Total K uptake of Suweon 258 was larger than that of Musashikogane, and in the latter plants K was obviously lost at the late growing stage.

Effect of Dietary Fat Supplementation on the Carcass Composition of Three Genetic Lines of Broilers

Three genetic lines of broilers – a commercial line (Ross × Arbor-Acres), and lines selected for low abdominal fat (lean line), and high abdominal fat (fat line) were fed one of two isocaloric and isonitrogenous purified diets differing in total fat content (2 vs. 9%). Carcass composition (crude protein, ether-extract, ash, and total dry matter content) was determined on four broilers/line/diet at 21 days of age and at 1 kg body weight. Carcass protein and ether-extract were not significantly (P<.05) affected by diet at 21 days of age or at 1 kg body weight. Carcass ash was significantly (P<.01) affected by diet at 21 days of age but not at 1 kg body weight. Genetic line of broiler significantly (P<.05) affected carcass protein, ether-extract, and ash at 21 days of age and at 1 kg body weight. Lean line broilers had a significantly (P<.05) higher percentage of carcass protein and a significantly (P<.05) lower percentage of carcass ether-extract than the fat line or commercial broilers.

ASSESSMENT OF AGRISPON, A MICROBIAL SOIL SUPPLEMENT, ON CEREAL PRODUCTION

Agrispon has been promoted in Western Canada as a soil supplement that provides plant-available nitrogen via undefined catalytic as well as microbial processes. Testing was undertaken in a controlled environment and under field conditions, to substantiate claims made by manufacturers and promoters that this product enhances germination and availability of nitrogen to plants. Characterization of the microbial composition of this product was also undertaken. Germination of Neepawa hard red spring wheat (Triticum aestivum L.) was not influenced in a greenhouse study. Growth chamber studies did not show any beneficial effect of Agrispon on total dry matter, grain yield or protein content of Neepawa wheat. Field studies with Canuck hard red spring wheat gave similar results to those obtained in the growth chamber i. e., no benefit in grain yield or protein content of Agrispon-treated plants. Analysis of soil samples taken at the end of the experiment also revealed no treatment effect of Agrispon or N fertilizer on available NO−3-N or NH4+-N levels. Microbiological determinations revealed relatively low populations of common soil organisms.Key words: Agrispon, Nitro/Max, soil supplement, bacterial population, fertilizer

Effect of sowing date, population density and row spacing on growth and yield of opium poppy in north central subtropical India

SUMMARYOpium poppy (Papaver somniferum Linn.) was sown at three sowing dates (10, 25 November, 10 December), row spacings (15, 30, 45 cm) and population densities (6 × 105, 3 × 105, 1·5 × 105 plants/ha) in a split-plot design at Lucknow. Sowing on 10 November resulted in higher yields of opium, seed, total dry matter and morphine content. Delayed sowing, higher plant density and narrow spacing produced low yields with less morphine content. Decline in opium yield was associated with decrease in plant height, leaf area index, capsule size and number of capsules per plant. The crop sown on 10 November removed most N. N concentration and uptake also increased when the number of plants per unit area was decreased. The study suggests that to achieve maximum yields poppy should be sown in rows 30 cm apart on 10 November with 3 × 105 plants/ha.

Activities of amylase, trypsin and lipase in the pancreas and small intestine of the laying hen during egg formation.

1. During a cycle of 14 h artificial light and 10 h darkness, dry matter and enzyme concentrations were measured in the pancreas and gut of egg-forming hens. 2. Dry or fresh pancreas weight did not show significant variation but pancreatic enzyme activities increased gradually from 2 to 22 h after oviposition. 3. Total wet and dry matter contents of the small intestine gradually increased from 2 to 18 h after oviposition and then decreased significantly. Intestinal tryptic activity followed the same pattern whereas intestinal amylase gradually decreased from 2 h after oviposition; intestinal lipase activity tended to decrease during the light period (2 to 10 h after oviposition) and to increase during the dark period (14 to 22 h after oviposition). 4. By contrast, patterns of enzyme activity in the pancreas were similar. It is proposed that modification of the chyme and transit rates during the day may affect pancreatic enzyme fate and distribution in the small intestine. 5. In non-egg-forming birds intestinal contents and enzyme activities were less than in egg-forming birds. The reverse was observed in the case of the pancreas where contents and enzyme activities were increased. A relationship with food intake pattern is discussed.