Proportion Of Dry Matter Research Articles

Hygienic Aspects of Cattle Slurry Storage as the Most Popular and Cheapest Method of Handling Liquid Animal Excrements / Higieniczne aspekty składowania gnojowicy bydlęcej jako najpopularniejszej i najtańszej metody postępowania z płynnymi odchodami zwierzęcymi

Abstract Slurry is a very valuable natural fertilizer, but its improper use in agriculture poses a serious sanitary threat. Therefore its treatment before use for fertilization is advisable. One of such methods, which is still the most popular, is storage of liquid excrements. The aim of this study was to estimate the sanitization effectiveness of storage at 4ºC and 20ºC based on parameters describing the kinetics of changes in the population of some indicator bacteria in cattle slurry with different dry matter content. The material for the study was fresh cattle slurry. The liquid excrements used in the experiment had a dry matter content of 2, 6 and 14%. Slurry was stored at 4ºC and 20ºC. Bacilli of Salmonella Dublin, E. coli and enterococci were used as indicator bacteria. Number of microorganisms was determined based on MPN method in a 3-tube design. Basic parameters of the bacteria inactivation kinetics were calculated and statistical analysis was made using the program SAS 9.2 PL. In stored slurry a gradual elimination of all the studied microorganisms was observed. Hygienization effect of storage was smaller at 4ºC than at 20ºC and in excrements with a high dry matter content. Depending on storage temperature and dry matter proportion, the theoretical times of survival ranged from 81.85 to 220.80 days for bacilli of Salmonella Dublin, from 74.93 to 199.36 days for E. coli, and from 118.67 to 335.84 days for enterococci. The study showed explicitly that statutory time of slurry storage is insufficient to ensure its complete hygienization.

Regrowth of spring canola (Brassica napus) after defoliation

Regrowth of dual-purpose canola after grazing is important for commercial success and the aim of this research was to investigate the effects of defoliation on the development, growth, photosynthesis and allocation of carbohydrates. We conducted two pot experiments in which defoliation was conducted at multiple intensities with scissors. Experiment 1 determined changes in flowering date due to defoliation while Experiment 2 investigated the effects of defoliation on growth, photosynthesis and allocation of carbohydrates in canola. Time to the appearance of the first flower was delayed by up to 9 days after the removal of all leaves at the start of stem elongation (GS30), and up to 19 days if the elongating bud was also removed. Stem growth rate decreased by 56–86 % due to defoliation and tap roots did not increase in mass when plants were completely defoliated. Leaf area continued to expand at the same rate as in un-defoliated plants. The new leaf area established per gram of regrowth biomass over 20 days was 158 cm2.g-1 for the complete defoliation treatments compared with 27 cm2.g−1 for the half-defoliated treatment and 13 cm2.g−1 for the un-defoliated treatment. Despite a reduction in total biomass of up to 60 %, the proportion of dry matter partitioned to the leaves was 18 % for all treatments within 20 days after defoliation. Total non-structural carbohydrate levels were reduced rapidly in the stem by day two (predominately sucrose) and the tap root by day four (predominately starch) after defoliation and did not recover to match un-defoliated plant levels within 20 days. Residual leaves on defoliated plants maintained photosynthetic rate compared with the same leaf cohorts on un-defoliated plants in which photosynthetic rate decreased to 39 % by day 12. The rapid recovery of leaf area in defoliated canola was facilitated by the sustained high photosynthetic rate in remaining leaves, rapid mobilisation of stored sugars (stem) and starch (root), and a cessation of root and stem growth.

Fruit productivity and carbon gain of Opuntia ficus-indica (L.) Mill. trees

Opuntia ficus-indica (OFI) tree and orchards efficiency has been poorly studied, in terms of relation between orchard lay out, light interception, and cropping efficiency. Apparently, there is no other way to increase orchard production than increasing the number either of trees ha-1 or fertile shoots tree-1, considering that a fruit count higher than 6-7 cladode-1 reduces fruit harvest size. The first option requires a reduction of unit tree size and canopy volume. The second option implies the use of large trees that often reduce their efficiency 12-15 years after planting. In 15-year-old OFI trees spaced 6 5 m apart trained to a globe and 2.5-3.0 m high, stem area index (SAI) calculated on the ground surface area covered by the tree was 2.9 and 6.5, respectively, for most active 1- and 2-year-old cladodes and whole canopy surface area. SAI orchard (cladode surface area/ground surface area allotted to the tree) values were slightly lower: 1.8 and 3.9. The proportion of annual dry matter allocated to the...

مطالعه کمی و کیفی تولید علوفه در کشت مخلوط کوشیا (Kochia scoparia L.) با ارزن پادزهری (Panicum antidotale Retz.) تحت شرایط آبیاری با آب شور

شوری خاک و آب آبیاری مشکلات عمده ای را برای تولید علوفه بوجود آورده است بنابراین این تحقیق با هدف بررسی کمی و کیفی تولید علوفه در کشت مخلوط کوشیا (Kochia scoparia L.) و ارزن پادزهری (Panicum antidotale Retz.) در شرایط آبیاری با آب شور به اجرا درآمد. هدایت الکتریکی آب آبیاری در طی دوره رشد 9/4 دسی زیمنس بر متر بود. این آزمایش در قالب طرح بلوک‌های کامل تصادفی با سه تکرار در سال زراعی 90-1389 در مزرعه تحقیقات شوری قطب علمی گیاهان زراعی ویژه دانشگاه فردوسی مشهد انجام شد. تیمارهای آزمایش متشکل از سه سطح مختلف (25، 50 و 75 درصد) از ترکیب نسبی دو گونه و دو تیمار تک کشتی بود. در بین تیمارهای مخلوط در مجموع دو چین، تیمار 50% ارزن و 50% کوشیا با میانگین 1408 گرم در مترمربع بیشترین عملکرد ماده خشک را داشت و پس از آن تیمار 25% ارزن و 75% کوشیا و تیمار 75% ارزن و 25% کوشیا به ترتیب با میانگین 1317 و 993 گرم در مترمربع قرار گرفتند. به علت رشد کمتر ارزن پادزهری (گیاهی چند ساله) در سال اول، سهم زیادی از عملکرد ماده خشک در هر تیمار، مربوط به کوشیا بود و در تمامی تیمارهای مخلوط، نسبت برابری زمین کمتر از یک بود. در چین اول و دوم، تفاوت معنی داری بین تیمارهای مخلوط از نظر درصد پروتئین خام، خاکستر، فیبر شوینده خنثی (NDF) و فیبر شوینده اسیدی (ADF) وجود نداشت. ولی با توجه به خصوصیات متفاوت کمی و کیفی علوفه این دو گیاه، تحقیقات بیشتر در این زمینه توصیه می شود.

Effect of feeding buckwheat and chicory silages on fatty acid profile and cheese-making properties of milk from dairy cows.

Fresh buckwheat (Fagopyrum esculentum) and chicory (Cichorium intybus) had been shown to have the potential to improve certain milk quality traits when fed as forages to dairy cows. However, the process of ensiling might alter these properties. In the present study, two silages, prepared from mixtures of buckwheat or chicory and ryegrass, were compared with pure ryegrass silage (Lolium multiflorum) by feeding to 3 × 6 late-lactating cows. The dietary dry matter proportions realised for buckwheat and chicory were 0.46 and 0.34 accounting also for 2 kg/d of concentrate. Data and samples were collected from days 10 to 15 of treatment feeding. Buckwheat silage was richest in condensed tannins. Proportions of polyunsaturated fatty acids (PUFA) and α-linoleic acid in total fatty acids (FA) were highest in the ryegrass silage. Feed intake, milk yield and milk gross composition did not differ among the groups. Feeding buckwheat resulted in the highest milk fat concentrations (g/kg) of linoleic acid (15.7) and total PUFA (40.5; both P < 0.05 compared with ryegrass). The concentration of α-linolenic acid in milk fat was similar across treatments, but its apparent recovery in milk relative to the amounts ingested was highest with buckwheat. The same was true for the occurrence of FA biohydrogenation products in milk relative to α-linolenic acid intake. Recovery of dietary linoleic acid in milk remained unaffected. Feeding buckwheat silage shortened rennet coagulation time by 26% and tended (P < 0.1) to increase curd firmness by 29%. In conclusion, particularly buckwheat silage seems to have a certain potential to modify the transfer of FA from feed to milk and to contribute to improved cheese-making properties.

How do dairy cows chew?—Particle size analysis of selected feeds with different particle length distributions and of respective ingested bolus particles

Not only feed but also respective bolus particle size could alter diet efficiency and cow performance. The objective of this project was to characterize particle size of selected feeds and respective swallowed boli. Feed samples included 6 different particle length rye grass hay samples, 1 grass silage, 1 corn silage, and 1 total mixed ration (TMR). Rye grass hay samples consisted of long hay and chopped hay particles retained on the 19- (19_PSPS hay), 8- (8_PSPS hay), and 1.18-mm (1.18_PSPS hay) Penn State Particle Separator (PSPS) screens and those collected on the pan (PSPS_pan hay). A sixth hay treatment was rye grass forage cut at 50-mm lengths and dried to hay (50-mm hay). Treatments were offered to 4 nonlactating and 4 lactating cows following rumen evacuation. Swallowed boli were collected and the number of chews per gram of ingested feed dry matter was determined. Feed and bolus particles of lengths ≥5mm were collected on a 1.6-mm screen using a horizontal wet sieving technique. This cut point was chosen, as the literature suggests that most fecal particles are shorter than 5mm. Dry matter proportions on this screen (PROP_1.6) were determined and particle lengths of retained particles were measured by image analysis. Mean particle lengths (ML) were calculated considering particles ≥5mm in length. Boli of long hay, of 19_PSPS hay, of 8_PSPS hay, and of 50-mm hay had similar ML of 10 to 11mm. Bolus PROP_1.6 were also similar between these treatments, ranging from 0.54 to 0.69. Bolus particle lengths and distributions of these treatments were not related to respective hay particles. Bolus of 1.18_PSPS hay had PROP_1.6 of 0.51 and a smaller ML of 8mm. The PSPS_pan hay had PROP_1.6 of only 0.33, but was still chewed intensely. Apparently, little particle size reduction occurred when cows ate the TMR or the silages. Feed and respective bolus PROP_1.6 were as follows: 0.66 and 0.59 in grass silage, 0.52 and 0.55 in corn silage, and 0.44 and 0.38 in the TMR. Feed and respective bolus ML were as follows: 13.8 and 11.6mm in grass silage, 12.0 and 11.2mm in corn silage, and 13.1 and 12.5mm in the TMR. Rye grass hay particles retained on PSPS screens ≥8mm, with ML of at least 25mm were longer compared with TMR particles, but respective bolus particles were shorter. Bolus particle size is not associated with the size of large feed particles chewed to a constant size that is appropriate for deglutition. This size may be related to feed chemical composition.

Using a mathematical framework to examine physiological changes in winter wheat after livestock grazing: 1. Model derivation and coefficient calibration

Existing crop-livestock models can largely be separated into two groups: those that simulate crop growth and grain yield with no grazing, and those that simulate pasture production during and after grazing but do not simulate grain yield. The purpose of this paper was to develop a crop-grazing model (hereafter, ‘WHTGRAZ’) capable of realistically simulating biophysical phenomena of grazed wheat crops in rainfed environments. This derivation revealed important physiological distinctions between typical crop simulation and changes in growth that occurred as a result of grazing, such as delayed phenological development.WHTGRAZ was based on the crop model SUCROS2, with modifications. The Penman approach to evapotranspiration simulation was adapted to the FAO Penman–Monteith method. Dry matter (DM) accumulation was modified from photosynthesis to radiation-use efficiency. Specific leaf area was modelled as a function of crop ontogeny, and rules for dead leaf decomposition and trampling of shoot DM were also added. Phenological delays induced by defoliation – and consequences thereof – were identified as a key determinant of growth after grazing, and were modelled as a function of temperature and the rate of shoot DM removal. Parameters were calibrated using measurements of phenology, soil water, shoot DM, and leaf area index from field experiments using two winter wheat cultivars and four grazing treatments.Two important physiological insights were gained from the derivation. First, accurate prediction (within one SEM) of shoot DM removal during grazing is a necessary prerequisite for accurate simulation of post-grazing shoot DM accumulation. Reasonable quantification of green leaf removal and trampling by livestock is needed because green leaf area governs light interception and growth in WHTGRAZ. Second, grazing-induced delays to phenological development cause greater proportions of shoot DM to be allocated to leaves during late vegetative development, decreasing the fraction of shoot DM that would otherwise be partitioned to stems. Delayed phenology of grazed crops also causes greater proportions of kernel DM to be sourced from post-anthesis photosynthesis, as opposed to DM retranslocated from stems.

Assessment of Groundnut under Combined Heat and Drought Stress

AbstractIn semi‐arid regions, particularly in the Sahel, water and high‐temperature stress are serious constraints for groundnut production. Understanding of combined effects of heat and drought on physiological traits, yield and its attributes is of special significance for improving groundnut productivity. Two hundred and sixty‐eight groundnut genotypes were evaluated in four trials under both intermittent drought and fully irrigated conditions, two of the trial being exposed to moderate temperature, while the two other trials were exposed to high temperature. The objectives were to analyse the component of the genetic variance and their interactions with water treatment, year and environment (temperature) for agronomic characteristics, to select genotypes with high pod yield under hot‐ and moderate‐temperature conditions, or both, and to identify traits conferring heat and/or drought tolerance. Strong effects of water treatment (Trt), genotype (G) and genotype‐by‐treatment (GxTrt) interaction were observed for pod yield (Py), haulm yield (Hy) and harvest index (HI). The pod yield decrease caused by drought stress was 72 % at high temperature and 55 % at moderate temperature. Pod yield under well‐watered (WW) conditions did not decrease under high‐temperature conditions. Haulm yield decrease caused by water stress (WS) was 34 % at high temperature and 42 % under moderate temperature. Haulm yield tended to increase under high temperature, especially in one season. A significant year effect and genotype‐by‐environment interaction (GxE) effect were also observed for the three traits under WW and WS treatments. The GGE biplots confirmed these large interactions and indicated that high yielding genotypes under moderate temperature were different to those at high temperature. However, several genotypes with relatively high yield across years and temperature environments could be identified under both WW and WS conditions. Correlation analysis between pod weight and traits measured during plant growth showed that the partition rate, that is, the proportion of dry matter partitioned into pods, was contributing in heat and drought tolerance and could be a reliable selection criterion for groundnut breeding programme. Groundnut sensitivity to high‐temperature stress was in part related to the sensitivity of reproduction.

Increasing the harvest index of wheat in the high rainfall zones of southern Australia

The harvest index (HI) of wheat in the high rainfall zones (HRZ) of Australia is low compared with values in similar rainfall environments in Europe. From 2005 to 2007, we examined dry matter (DM) partitioning, yield formation, post-anthesis dry matter accumulation, and remobilization of water soluble carbohydrates (WSC) of a number of wheat genotypes (5 spring wheat and 1 winter wheat) to determine the factors influencing the HI in the HRZ of south-western Australia. Grain yield was strongly correlated with grain number (GN) in all three years and with the sum of post-anthesis DM accumulation and WSC in stems at anthesis when the amount of assimilates available to fill grains was less than 600gm−2. However, when the amount of assimilates exceeded 600gm−2, grain yield reached a plateau and did not increase with the increased availability of assimilates because of sink limitations. Genotypes with more GN tended to extract more WSC to fill grains than ones with fewer GN in 2005 and 2007. GN increased with increased spike DM at anthesis, the number of grainsg−1 of spike DM, and the duration of spike growth, but was not correlated to the fraction of DM partitioned to the spike at anthesis for individual genotypes and across the 3 years. Compared to winter wheat in the UK, Australian spring and winter wheat had a lower number of grainsg−1 spike DM and g−1 chaff DM. HI was positively related to WSC at anthesis and post-anthesis DM accumulation in the drought year of 2006, but not in average (2007) and above-average rainfall (2005) years. HI was negatively related to the proportion of stem DM to above-ground dry matter (AGDM), but positively related to the proportion of spike DM to AGDM. Dry matter partitioning indicated that the proportion of stem DM to AGDM and chaff DM to AGDM was 20% and 50% higher than that of winter wheat grown in the UK, respectively. This was related to a lack of remobilization of WSC and a net increase between spike DM at anthesis and chaff DM at maturity. Therefore, we suggest that increasing the number of grainsm−2 by breeding for more grainsg−1 spike DM, reducing dry matter partitioning into stem and chaff, and remobilizing WSC can lead to an improved HI. We conclude that the yield of wheat can be increased without increasing AGDM and the potential HI can reach 0.50 in the HRZ of south-western Australia if the number of grainsm−2 can be increased.

Relationships between moisture, chemistry, and ignition of Pinus contorta needles during the early stages of mountain pine beetle attack

Very little is known about how foliar moisture and chemistry change after a mountain pine beetle attack and even less is known about how these intrinsic foliar characteristics alter foliage ignitability. Here, we examine the fuel characteristics and ignition potential of Pinus contorta (lodgepole pine) foliage during the early stages of a mountain pine beetle attack. Foliar samples were taken periodically from multiple trees identified as green (healthy, unattacked), recently attacked, or red (dead). The fuel moisture content, chemical composition, and time to ignition of needles from each attack category were quantified. Foliar moisture contents varied by an order of magnitude between the attack categories and were lowest for red needles (∼12% on average), highest for green needles (∼109% on average), and most variable for needles of recently attacked trees. Dry matter proportions of fiber in the needles of attacked and red trees were nearly twice that of green needles. Starch and sugar levels were much lower in the needles of attacked and red trees than green trees. Crude fat contents also differed between the attack categories. Time to ignition was strongly related to time since beetle attack. Ignition times varied from as little as 11s for red needles to 41s for green needles. A combined model of foliar moisture content, fiber, and crude fat explained 92% of the variation in the foliar time to ignition. Results show that decreased moisture contents and changes in foliar chemistry increase the foliar flammability of mountain pine beetle-attacked trees. This suggests that less heat would be required to ignite the foliage of attacked trees and thus crown fire potential may be higher in attacked stands as long as foliage is retained on the tree.

Silages containing buckwheat and chicory: quality, digestibility and nitrogen utilisation by lactating cows

The suitability of silages containing buckwheat (Fagopyrum esculentum) and chicory (Cichorium intybus) for the nutrition of dairy cows was determined. Buckwheat and chicory were sown in mixture with ryegrass (Lolium multiflorum), and a pure ryegrass culture served as a control forage. Swards were harvested 55 d after sowing and were ensiled after wilting, without additives in small round bales. Finally, buckwheat and chicory made up the dietary dry matter (DM) proportions of 0.46 and 0.34, respectively. Concentrates were restricted to 2 kg/d. Diets were fed to 3 × 6 late-lactating cows for 15 d at ad libitum access. During the collection period (days 10–15) amounts of feed intake and faeces, urine and milk were recorded and samples were taken. Ensilability was good for buckwheat and ryegrass swards, but was so less for the chicory sward, which was rich in total ash. The buckwheat silage was rich in acid detergent fibre (445 g/kg DM) and lignin (75.7 g/kg DM) and contained less crude protein (135 g/kg DM) and ether extract (15.8 g/kg DM) than the other silages. Consistent with that, the apparent digestibility of the organic matter and fibre were lowest when feeding this silage. The potassium concentrations in the chicory and ryegrass silages were high (61 g/kg) and lower in buckwheat (47 g/kg). No significant treatment effects on intake, body weight, milk yield or milk composition as well as plasma β-hydroxybutyrate and non-esterified fatty acids occurred. Being lowest in nitrogen (N) content, the buckwheat silage resulted in the lowest urine N losses and the most efficient N utilisation for milk protein synthesis, but this at cost of body N retention. The results show that silages containing buckwheat and chicory may be used as components of the forage part of dairy cows’ diets even though they were found to have a lower feeding value than ryegrass silage.

Use of Grasses and Mixtures of Grasses for Energy Purposes

As levels of agricultural productivity increase, there is also an increase in land area not utilized for food production. This area can be used for growing energy crops, including grasses. When land is set aside for grassing, or when the potential of perennial grasses is not utilized due to reductions in cattle herds, there is also an increased amount of grass that can be utilized for energy purposes. Experiments were carried out on the principle of single-stage anaerobic digestion within the mezophyle range. During the experiments, we measured the cumulative production of biogas and its composition. The processed grass was disintegrated by pressing and cutting. This adaptation of the material resulted in increased biogas production. The optimum proportion of grass dry matter is from 35 to 50 % in the total d.m. The results of the experiments proved the suitability of grass phytomass as a material for biogas production.

Effect of grinding size and sunflower oil addition on intake, digestibility, rumen function and microbial protein synthesis in sheep fed a dry total mixed ration

An experiment was carried out in which the effect of grinding a dry total mixed ration, based on barley straw, through 6 or 10 mm sieves on intake, digestibility, rumen function and microbial protein synthesis in sheep was assessed. The effect of including 1% sunflower oil as binder was also explored. None of the variables studied was affected by grinding size, hence the 10 mm sieve was recommended due to its lower cost in terms of energy consumed. On the contrary, addition of 1% sunflower oil significantly increased ammonia concentration in the rumen (83 vs. 161 mg L–1; p = 0.002), potential degradabilities (as proportion) of dry matter (0.65 vs. 0.75; p = 0.0037), organic matter (0.68 vs. 0.75; p = 0.0005) and crude protein (0.78 vs. 0.90; p = 0.0004), and fractional rate of degradation (0.066 vs. 0.080 h–1; p = 0.046) and effective degradability, as proportion (0.63 vs. 0.73; p = 0.010), of this latter. Oil addition (1%) is then recommended as binder, although a more economical option than sunflower oil should be explored due to its high cost.

Integrated recirculating foam fractionation for the continuous recovery of biosurfactant from fermenters

A novel foam fractionation design has been developed for continuously recovering extracellular biosurfactants from fermenters. The apparatus design allows for the operating conditions of the foam fractionation process, feed rate and airflow rate, to be chosen independently of the fermentation parameters. Optimal conditions can then be established for each process, such as the aeration rate required to meet the biological oxygen demand of the cell population. The recirculating foam fractionation process was tested on fed batch fermentations producing the hydrophobin protein HFBII. It is shown that by using foam fractionation to strip HFBII from fermentation broth in situ the amount of uncontrolled overflow from the fermenter was greatly reduced from 770 g to 44.8 g, compared to previous fermentations without foam fractionation. Through optimisation of the foam column operating conditions the proportion of dry matter retained in the fermenter was increased from 88% to 95%, in contrast to dry matter retention of 66% for fermentation without the new design. With the integrated foam fractionation process an HFBII recovery of 70% was achieved at an enrichment of 6.6. This study demonstrates the utility of integrated foam fractionation in minimising uncontrolled foaming in fermenters whilst recovering an enriched product.

Variability in feed and total mixed ration neutral detergent fiber and crude protein analyses among commercial laboratories

The objective of this study was to assess the variability in amylase-treated neutral detergent fiber (aNDF) and crude protein (CP) analyses of feed and total mixed ration (TMR) samples among feed analysis laboratories. Two TMR were prepared that varied in the dry matter proportion of forage and concentrates: 45% forage (LF-TMR) versus 60% forage (HF-TMR). Replicated TMR and individual feed samples were dried, ground through a 4-mm screen, and sent to 10 commercial and 4 research or development laboratories for aNDF and CP analyses. Laboratories were asked to complete a detailed questionnaire regarding the aNDF procedure used. Variability in aNDF and CP analyses was assessed using univariate statistics and mixed modeling procedures. Significant variability in the aNDF analysis of individual feeds was found among the participating laboratories. The variability was particularly large for low-aNDF feeds such as distillers and barley grains. The variability among laboratories in the aNDF analysis of low-fiber TMR was greater than of high-fiber TMR, with the most likely reason being their greater proportions of grains and protein concentrates and the effect of variation in the aNDF protocols, particularly α-amylase use, on the analysis of these types of feeds. Variability due to the technique used for aNDF analysis was not statistically significant when outlier labs using the filter bag technique were removed; however, laboratories using the filter bag technique tended to produce more variable results than did laboratories using variation of the crucible technique (SE=2.542 vs. 0.930, respectively). Calculated aNDF values for TMR, based on proportions and aNDF analysis of individual feeds, were slightly greater than analyzed aNDF values for TMR. Results from this ringtest emphasize the need for feed analysis laboratories to follow the official aNDF method exactly. Variation within and among laboratories can be reduced by replicating analysis and including reference materials in each analytical run. Results of CP analysis were more consistent among laboratories, and variability in CP analysis of individual feeds or TMR was marginally acceptable.

GROWTH AND BIOMASS OF TWO-YEAR-OLD SEEDLINGS OF EUROPEAN CHESTNUT DERIVED FROM THE HALF-SIB FAMILIES OF DIFFERENT ORIGIN

In the spring of 2005, seeds collected in twelve different half-sib families being at the age of 40 years and originated from mother trees grown on four different localities of Slovakia were used to established an experimental plot in the forest nursery Hladomer, Slovakia. At the age of 2 years, in each of 12 sets of seedlings 15 seedlings differing in growth performance were selected (5 from each replication) and subjected to morphometric analysis. In each seedling 5 biometric characteristics (stem height, stem diameter, root length, root diameter, diameter of the root collar), 3 single biomass characteristics (biomass of the stem and branches, root biomass, leaf biomass), 2 combined biomass characteristics (aboveground biomass and total seedling biomass) and three derived parameters (index of annual stem height increment, index of annual stem diameter increment and foliage ratio -proportion of leaf dry matter and total dry aboveground matter of the seedling) were evaluated. All characteristics under study except indices and foliage ratio exhibited significantly highest mean values in the seedlings derived from three half-sib families of Horne Lefantovce origin, particularly from the HL A family. The seedlings derived from this family showed significantly highest values of aboveground and underground biomass but the second lowest foliage ratio. This suggests the high effective use of leaves for biomass production in these seedlings. Foliage ratio was in medium strong negative correlation with most of the growth and biomass characteristics.

Dry Matter and Nutrient Partitioning of Selected Pineapple Cultivars Grown on Mineral and Tropical Peat Soils

The pineapple cultivars ‘Moris’ (Queen cultivar), ‘N‐36’ (‘Sarawak’ × ‘Gandul’ hybrid), ‘Gandul’ (Singapore Spanish cultivars), and ‘Josapine’ (‘Singapore Spanish’ × ‘Smooth Cayenne’ hybrid) are mostly grown on peat soils in Malaysia, whereas ‘Sarawak’ (‘Smooth Cayenne’ cultivar) is more commonly grown on mineral soils. To obtain good yields of fruit of high quality, it is important to understand the differences in nutrient requirements for these cultivars in the different soils in which they are grown. Therefore, the objectives of the study were to determine the biomass and nutrient partitioning of the different pineapple cultivars and to determine the plant variables affecting fruit yield and quality. Plants of each of the pineapple cultivars were randomly sampled from different locations of the major pineapple‐growing areas in Malaysia. Only plants having A‐grade fruit of marketable quality at harvest were selected. The cultivars and respective field sites were as follows: ‘Sarawak,’ Bukit Tandak farm, Kelantan (5° 55.274′ N, 102° 00.608′ E); ‘Moris,’ ‘N‐36,’ and ‘Gandul,’ Peninsula Pineapple Plantations, Simpang Renggam, Johor (1° 49.909′ N, 103° 14.053′ E); and ‘Josapine,’ Goh Swee Eng Pineapple Farm, Simpang Renggam, Johor (1° 48.441′ N, 103° 11.935′ E). Plants were partitioned into roots, stem, leaves, peduncle, fruit, and crown, and fresh and dry weights were recorded. Total biomasses for the different cultivars were 733.46 ± 22.83 g for ‘Gandul,’ 842.34 ± 43.26 g for ‘N‐36,’ 927.38 ± 53.10 g for ‘Moris,’ 434.77 ± 16.82 g for ‘Josapine,’ and 2446.94 ± 156.00 g for ‘Sarawak.’ Leaves accounted for the greatest proportion of dry matter (48.5%), followed by fruit (22.9%) and stem (21.6%), and a smaller proportion (1.2–2.5%) was roots, peduncle, and crown. The proportions of the dry‐matter accumulation in leaves and stem for the cultivars were 53.5 ± 0.7 and 16.7 ± 0.9% for ‘Gandul’; 45.1 ± 0.5 and 17.7 ± 0.7% for ‘N‐36’; 51.9 ± 1.6 and 16.8 ± 0.6% for ‘Moris’; 56.5 ± 1.0 and 12.0 ± 0.9% for ‘Josapine’; and 54.2 ± 5.1 and 27.7 ± 4.4% for ‘Sarawak.’ The proportion of the macro‐ and micronutrients in pineapple parts differed widely between cultivars. Potassium (K) showed the greatest proportion (7.96 ± 0.6 to 29.73 ± 1.17%) in leaves and (4.46 ± 0.70 to 9.35 ± 0.28%) in fruit followed by nitrogen (N) and phosphorus (P) with lower proportions. Most pineapple cultivars grown showed variation in nutrient‐use efficiency (NUE) with respect to the elements measured with values of <1.0 g dry matter g−1 nutrient. The NUE values of >1.0 g dry matter g−1 nutrient were observed for magnesium (Mg) in ‘Gandul’ and ‘N‐36’ and for calcium (Ca) and copper (Cu) in ‘N‐36.’ Total nutrient accumulation in the plant components differed approximately according to their cultivar origins (‘Smooth Cayenne,’ ‘Queen,’ ‘Singapore Spanish’). It is interesting that the results for the ‘Singapore Spanish’ × ‘Smooth Cayenne’ hybrid Josapine were more similar to the ‘Singapore Spanish’ cultivars than being between the parents. Partitioning of biomass and nutrients in pineapple provides a means to categorize them and makes it possible to use a cultivar‐based fertilization program.

Potassium Uptake and Partitioning Relative to Dry Matter Accumulation in Cotton Cultivars Differing in Maturity

Dry matter may accumulate faster in fruit of earlier maturing cotton (Gossypium hirsutum L.) cultivars than in later cultivars, requiring more rapid K uptake and/or partitioning to developing bolls. Faster K uptake may require higher K fertility. We examined K uptake and partitioning relative to dry matter accumulation during boll filling of two cultivars contrasting in maturity, under two K fertility regimes at Jackson, TN. Plots fertilized with 56 kg K ha−1 yr−1 received the recommended rate of K, while plots receiving 112 kg K ha−1 yr−1 were overfertilized with K. ‘PM 1218 BG/RR’ (PVP 200000213) matured earlier than ‘DP 555 BG/RR’ (PVP 200200047) in 2005, and ‘FM 960BR’ PVP 200400224 matured earlier than DP 555 BG/RR in 2006, but not 2007. Higher K fertility did not increase lint yields, but it delayed maturity in two of 3 yr. During boll filling, the earlier cultivar accumulated more dry matter and K in fruit than the later cultivar, and accumulated them faster in 2 of 3 yr. Higher K fertility shifted the partitioning of dry matter and K to vegetative organs relative to fruit. The proportion of plant K in fruit exceeded the proportion of dry matter in fruit, and the difference increased during boll filling. Evidently, K translocation to fruit exceeded dry matter accumulation in fruit, indicating that boll filling was not limited by K. Neither the K‐uptake ratio (total aboveground K relative to residual soil K plus fertilizer K) nor the K‐utilization ratio (lint produced per unit plant K) differed between cultivars with sufficient K fertility.

Response of Onion(Allium cepa L.) to Nutrient Sources and Weeding Regimes in Sudan Savannah

Onion is an important vegetable in Nigeria, but its production and quality are often low due to inappropriate agronomic practices like good nutrient sources and proper weed control. A study was carried out for two years to investigate the response of onion ( Allium cepa L.) to nutrient sources and weeding regimes on the bulb quality during 2006/2007 and 2007/2008 seasons at Sabke Dam, Katsina State (12o56’ N;7 o45’E). The experiment consisted of five sources of nutrients(mineral fertilizer, poultry droppings, rumen content, farm yard manure and no fertilizer as control) and four hoe weeding regimes at 3, 6, 9 weeks after transplanting(WAT) and weedy check as control. The treatments were arranged in a randomized complete block design with three replications. Results indicated that poultry droppings significantly produced higher proportion of marketable bulbs, soluble solids and dry matter as well as high cured bulb weight and bulb yield compared to other nutrient sources in both years. The control recorded the least in respect of all quality characters studied. Weeding regimes significantly (P weight in 2007/2008. Good quality marketable bulbs of onion was best obtained from poultry droppings in combination with weeding at 6 WAT

Weed Management in Aerobic Rice in Northwestern Indo-Gangetic Plains

Aerobic rice systems, wherein the crop is established via direct seeding in non-puddled, non-flooded fields, are among the most promising approaches for saving water and labor. However, aerobic systems are subject to much higher weed pressure than conventionally puddled transplanted rice (CPTR). Experiments were conducted for two years to develop effective and economical methods for managing weeds in aerobic rice grown by direct seeding rather than by conventional transplanting method. The proportion of mean grass-weed dry matter was 28.3% more in aerobic direct-seeded rice (ADSR) as compared to CPTR. Both weed density and dry weight were negatively correlated with rice grain yield. ADSR treatment produced yield similar to CPTR treatment when weeds were controlled effectively. Post-emergence application of bispyribac Na 25 g/ha and penoxsulam 25 g/ha could effectively control all the weeds in ADSR. Irrigation water productivity remained statistically the same in both ADSR and CPTR under the weed-free situation or when bispyribac Na herbicide was applied as post-emergence because of effective weed control in ADSR. The variation in net profitability between the ADSR and CPTR decreased with herbicide treatments, viz., Bispyribac Na, followed by penoxsulam and sequential application of pretilachlor and metsulfuron.