Weed Science Commons^™

Quality And Nutritive Value Of Mott Dwarf Elephantgrass Silage With Biological Additives, T. Clavero

IGC Proceedings (1977-2023)

This experiment was conducted to study the effects of cellulase enzymes and lactic acid bacteria on the fermentation characteristics, chemical composition and nutritive value of Pennisetum purpureum cv Mott silage. Five kinds of preparation were tested: sugar molasses (control); sugar molasses and cellulase enzymes; cellulase enzymes; concentrate of lactic acid bacteria and sugar molasses and concentrate of lactic acid bacteria. Significant differences (P< 0.05) were found in fermentation quality and chemical composition of control silage as compared to the biological additives treated silage. Addition of cellulase enzymes and lactic acid bacteria resulted in decrease of pH value, cell wall content and increased lactic acid concentration. The biological additives increased silage intake and daily live weight by growing steers.

Effects Of Different Additives On Silage Quality Of Napiergrass, Y. K. Cheng, C. S. Chen, P. W. Peng

IGC Proceedings (1977-2023)

Objectives of this experiment were to determine the effects of different additives on silage quality of napiergrass (Pennisetum purpureum). The cultivar of TLG2 with high water soluble carbohydrates was used to making silages added with or without 5 and 10% corn meal or wheat bran, and then treated with or without enzyme. Crude protein, acid detergent fiber, neutral detergent fiber, water soluble carbohydrates and volatile fatty acid contents of silage were determined to evaluate silage quality. From the results, it showed that var.TLG2 could be making good silages without any additives but the dry matter was low. Adding …

Utility Of Anaerobic Soil Disinfestation For Weed And Disease Management In Solanaceous Vegetable Crops, Gursewak Singh

All Theses

Managing weeds is one of the most challenging aspects of growing specialty crops. Weed control options are limited for specialty crops due to absence of effective herbicide options. The limited current herbicide options risk carryover and damage to subsequent crops. Bacterial wilt is another problem causing significant yield losses in southeast vegetable production. After the termination of methyl bromide due to health and environmental concerns, several other chemical fumigants gained interest, including 1,3-dichloropropene, chloropicrin and metam sodium/potassium. While less toxic to the environment than methyl bromide, these fumigants pose carcinogenic and mutagenic threats. Alternative weed control and diseases management tactics …

The Impact Of Beneficial Organisms In Corn Agroecosystems, Callie Rosalind Braley

Doctor of Plant Health Program: Dissertations and Student Research

Corn is one of the world’s, and Nebraska’s, most important crops. Millions of acres are planted to corn each year in the Cornhusker State. However, each year there are a plethora of arthropod, weed, and microorganism pests that rob farmers of reaching their maximum yield potential. There are many options available to manage these pests in corn agroecosystems, but one option is often underutilized: beneficial organisms. For each pest, there are a variety of natural enemies that can assist in mitigating the damage caused by pests.

Many beneficial organisms exist, and they can be grouped by the type of pest …

Skeleton Weed In Western Australia: Management Guide, Department Of Primary Industries And Regional Development

Bulletins 4000 -

Skeleton weed is a declared plant which can reduce crop yields by competing for moisture and nutrients (mainly nitrogen).

This Management Guide has been designed to assist landholders and increase their capacity to manage and eradicate skeleton weed infestations on their properties and to prevent further spread within the State. Without the coordinated program aimed at controlling spread, skeleton weed would now be much more abundant and widely established throughout the cereal growing areas.

Skeleton Weed In Western Australia Control Program 2021/22, Department Of Primary Industries And Regional Development

Bulletins 4000 -

The Program now includes:

• Recommendations for control in legume based annual pastures.

• Provision of clopyralid (Lontrel™) herbicide to eligible landholders, to undertake their own spraying of paddocks that are greater than 10% infested (by area), and known as heavily infested paddocks, has been retained (introduced in 2019/20).

Mitigating Rice Injury Caused By Florpyrauxifen-Benzyl And Optimizing Florpyrauxifen-Benzyl Rate And Timing For Use In Furrow-Irrigated Rice, James Winston Beesinger

Graduate Theses and Dissertations

Florpyrauxifen-benzyl (synthetic auxin, WSSA Group 4) is a postemergence, broad-spectrum herbicide labeled for use in Mid-South rice (Oryza sativa L.) production. Introduction of florpyrauxifen-benzyl to Arkansas rice production led to observations of varying levels of injury caused by the herbicide across cultivars and environments. Findings from previous research indicated hybrid long-grain rice and medium-grain rice were more susceptible to florpyrauxifen-benzyl and hypotheses were formed using this research regarding the impact of environmental conditions on the amount of injury observed. Concerns of yield loss, delay in maturity and loss of groundcover as well as questions regarding the ability of florpyrauxifen-benzyl to …

Integrated Weed Management Strategies For Palmer Amaranth (Amaranthus Palmeri) In Cotton And Soybean Production Systems, Rodger Bruce Farr

Graduate Theses and Dissertations

Management of Palmer amaranth [Amaranthus palmeri (S.) Wats.] in the Midsouth in soybean [Glycine max (L.)] and cotton (Gossypium hirsutum L.) production systems has become increasingly troublesome due to resistance to many of the commonly utilized herbicides in these systems. Developments have been made to utilize new chemistries as well as incorporate integrated weed management strategies to control Palmer amaranth, but questions have risen given the economic feasibility or effectiveness of these new strategies. Additionally, regulation has limited producers’ abilities to utilize some herbicide chemistries. As a result, experiments were conducted to 1) understand the utility of isoxaflutole in isoxaflutole-tolerant …

Palmer Amaranth [Amaranthus Palmeri (S.) Wats.] Resistance To S-Metolachlor In The Mid-Southern Us And S-Metolachlor Dissipation In Soil, Koffi Badou Jeremie Kouame

Graduate Theses and Dissertations

Palmer amaranth [Amaranthus palmeri (S.) Wats.] presents both a high genetic diversity and propensity to evolve resistance to herbicides of several sites-of-action which have made it one of the worst weeds in US agriculture. In Arkansas, Palmer amaranth is resistant to herbicides of seven sites-of-action, which are 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) inhibitor, acetolactate synthase inhibitors, microtubule inhibitors, protoporphyrinogen oxidase inhibitors, very long chain fatty acid inhibitors, glutamine synthetase inhibitors, and hydroxyphenylpyruvate dioxygenase inhibitors. Sustainable management requires a better understanding of its biology and that of herbicide environmental fate. This research had five objectives: 1) characterize the current status of Palmer amaranth …

Optimization And Resistance Mitigation Of Dicamba And Glufosinate In Xtendflex® Crops, Grant Lawson Priess

Graduate Theses and Dissertations

The commercial launch of XtendFlex® crops enabled the use of dicamba, glufosinate, and glyphosate in-season. Utilizing herbicides that target different sites of action within troublesome weeds has been a tactic proposed to mitigate the likelihood of target-site resistance evolving; however, if interactions of the herbicides are detrimental to control of weedy species the likelihood of metabolic resistance increases. The objective of this research was to: 1) optimize efficacy and economic benefits of dicamba, glufosinate, and glyphosate; 2) characterize any interactions that were observed; 3) understand the mechanisms responsible for the reductions in weed control; 4) attempt to overcome interactions that …

Forage Production From Perennial Vs. Annual Crop R~ On In Sandy Soils In Egypt, Z. Abdelhalim, O. Niemeläinen, I. A. Hanna, A. M. Rammah

IGC Proceedings (1977-2023)

Forage production was studied on newly reclaimed sandy soil in Egypt trom perennial lucerne (Medicago sativa L.) and two annual crop rotations. The cropping systems were: A) lucerne, B) berseem clover (Trifolium alexandrinum L.) in the winter followed by pearl millet (Pennisetum glaucum R. Br. Emend. Stantz.) in the summer and C) triticale (XX Triticosecale Wittm.) (forage cut + grain harvest) in the winter followed by maize (Zea mays L.) (grain + stover) in the summer. Mean annual dry matter yields (t ha^-1 ) were 20.65, 26.59 and 27.48 from A, B and C, respectively. However, …

Carry-Over Effect In Forage Rotations On Newly Reclaimed Sandy Soil In Egypt, Z. Abdelhalim, O. Niemeläinen, I. A. Hanna, A. M. Rammah

IGC Proceedings (1977-2023)

This study was carried out to investigate the carry-over effect of a preceding crop on the productivity of the following crop in various rotations in newly reclaimed lands in Egypt. The productivity of peanut (Arachis hypogaea L.), soyabean (Glycine max (L.) Merr.), maize (Zea mays L.) and pearl millet (Pennisetum glaucum (L.) R. Br.) in summer season were much higher following berseem (Trifolium alexandrinum L.) or lentil (Lens culinaris Medic) than after wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.) in both years of the study. Soyabean was the best summer …

Direct Drilling Of Soybean In A Pensacola Bahiagrass Pasture In The Northwest Region Of Rio Grande Do Sul, Brazil, R. B. Medeiros, J. Riboldi, J. C. De Saibro, J. E. G. Zambra

IGC Proceedings (1977-2023)

The response of methods of soil preparation (M₁=conventional tillage, and with notillage using the following herbicides M₂=50% Paraquat plus 50% Orizalin; M₃=50% Paraquat plus 50% Diquat and M₄=Paracol (20% Paraquat plus 20 Diuron)) and row spacing (E₁=17 cm, E₂=24 cm, E₃=51 cm and E₄=68 cm) on soybean grain yield direct drilled in an eight-year-old grazed sward of Bahiagrass cv. Pensacola (Paspalum notatum var. saurae Parodi) were studied in southern of Brazil. The results showed that direct drilling of soybean on Pensacola accompanied by …

Forage Quality Evaluation Of Chopped Elephantgrass Hay Through Intake And Digestibility Trial, E. M. De Aguiar, G. F. Da C. Lima, L. G. Da Paz

IGC Proceedings (1977-2023)

The research was carried out to evaluate forage quality of chopped elephantgrass (Pennisetum purpureum Schum.) hay and to define a proper stage for cutting and haymaking of this grass. Chemical composition, voluntary intake, and apparent digestibility of the hays were studied at five different growth stages (30, 48, 63, 76, and 91 days). Twenty-five common wethers were utilized in a completely randomized experimental design. Dry matter (DM) voluntary intake was not different (P> 0.05) from 30 to 63 days of regrowth and from 63 to 91 days and comprised 3.9; 3.5; 3.2; 2.1; and 2.4% of animal liveweight, respectively …

Berseem Clover In Binary Mixtures With Oats, Triticale Or Barley For Silage And Late Season Grazing, S. M. Ross, J. R. King

IGC Proceedings (1977-2023)

An experiment was conducted at northerly latitudes with berseem clover (Trifolium alexandrinum L) in binary mixtures with oats (Avena sativa L.), barley (Hordeum vulgare L.) and triticale (X Triticosecale Wittmack). The effects of cereal species, variety and density were assessed for a two cut harvest. Total dry matter yields were 11.7 to 14.5 t ha^-1, with 7.8 to 10.2 t ha^-1 as silage, and 2.0 to 6.0 t ha^-1 as berseem regrowth. Berseem regrowth added an average of 4.0 t ha^-1 in forage yield. Total yields did not differ with cereal …

Forage Productivity Of Panicum Maximum Pastures In Two Different Agropastoral Systems, Tsutomu Kanno, Manuel C. M. Macedo, J. A. Bono, J. D. G. Santos Jr., M. R. Correa, L. G. R. Beretta

IGC Proceedings (1977-2023)

Forage productivity was evaluated for Panicum maximum pastures established after 4 years of soybean cultivation in the summer (PM-SO), and 4 years of rotation of soybeans in the summer and millet for winter grazing (PM-MI). In the PM-MI pasture, biomass and dry matter production were much lower than in the PM-SO, and the amount of copper and nitrogen in the top part of the plants in PM-MI were significantly lower than that in PM-SO. Thus, it was considered that the shortage of copper and nitrogen restricted photosynthesis and forage production in PM-MI.

Nitrogen Mineralization From Root Residues Of Subterranean Clover And Lucerne, T. P. Bolger, J. F. Angus, M. B. Peoples

IGC Proceedings (1977-2023)

To understand why crops grown in the first or second year after lucerne (Medicago sativa L.) yielded less than crops grown after subterranean clover (Trifolium subterraneum L.) despite greater nitrogen (N) fixation by the lucerne, we studied the N mineralization patterns of their root residues in soil incubation assays. Fine roots of both species produced more mineral N than the control soil with no root residues. In contrast, coarse roots mineralized less N than the control soil. These differences in N mineralization were not explained by the physical size and therefore surface area differences between fine and coarse …

Transgenic Maize Hybrid Crop Residues: Nutritive Value And Their Effects On Performance Of Grazing Beef Cows, S. K. Barnhart, J. R. Russell, M. J. Hersom, D. E. Farnham

IGC Proceedings (1977-2023)

Several maize (Zea mays) hybrids, including three transgenic hybrids containing Bacillus thuringiensis (Bt) enzymes (Bt-maize hybrids), were planted in a field study. Mature, midgestation, beef cows (Bos tarus) strip-grazed post-harvest residues as paddocks over 126 days. Body condition-scores and weights were monitored. Forage yield, weathering losses and forage composition were monitored on grazed and ungrazed areas. Forage selection and intake were estimated. Grain yields, dropped grain, initial crop residue concentrations of dry matter (DM), organic matter (OM) and in vitro digestible organic matter (IVDOM) yields were similar among hybrids. Hybrids varied in infestation of maize borers, …

Supplementation Of Temperate Pastures, D. H. Rearte, G. A. Pieroni

IGC Proceedings (1977-2023)

Generally in temperate regions, beef and milk were produced on extensive systems with forage from perennial pasture and natural grassland being the main component of animal diet. Supplementation on pasture was usually applied strategically to supply nutrients to grazing cattle only when forage availability was not enough to satisfy animal’s requirements. At present beef and dairy production systems have become more intensive and even when forage from pasture continue being the main component of the diet higher level of different type of supplement are fed to the animals. Intensive systems are characterized by a higher stocking rate capable of consuming …

Feeding Of Conserved Forage - Implications To Grassland Management And Production, C. W. Holmes, P. N. P. Matthews

IGC Proceedings (1977-2023)

This review will focus on the use of conserved forages in pastoral dairy farm systems; especially on their conservation as an aid to good grazing management during periods of rapid pasture growth, and on their consumption as an aid to good feeding management and grazing management during periods of slow pasture growth. Conservation of pasture, in order to move it from one time to another later time, always involves “costs”, either financial expenditure or physical losses (of dry matter/quality) or both, which must be evaluated in the whole system.

Most of the data is drawn from New Zealand and Australia, …

Protein Sources For Growing Beef Steers Fed With A Diet Based On Corn Silage, M. De León, E. Ustarroz, C. Boetto, J. M. Simondi, M. Bulaschevich

IGC Proceedings (1977-2023)

This study was conducted to determine the effect of different protein sources in growing beef cattle (25 Aberdeen Angus steers) fed with a corn silage based diet on daily live weight gain (DLWG), dry matter intake (DMI) and feed conversion (FC). Five treatments with different supplies of crude, degradable and metabolizable protein (MP) were used. The treatments were formulated with different protein sources to provide different rate and extents of protein degradation, as follow: a negative control (T0) without protein supplements and below animal requirements, urea (T1), soybean meal (T2), whole cotton seed (T3) and a positive control (T4), which …

High Moisture Sorghum Grain Silage: Effects Of Tannin Content And Urea Treatment On The Performance Of Dairy Cows, L. A. Romero, E. A. Comerón, O. A. Bruno, A. R. Castillo, M. C. Gaggiotti

IGC Proceedings (1977-2023)

Grain sorghum silage tannin content effect was evaluated on milk production and chemical composition of Argentinean Holstein bred cows, and it are described dry matter (DM) and crude protein (CP) in situ digestion parameters and effective degradability. The base diet was constituted by alfalfa pasture, maize silage, and a protein – mineral supplement, differing in three treatments based on high moisture grain silage characteristic: LTS= Low tannin grain sorghum, HTS= High tannin grain sorghum, and HTSu= High tannin sorghum plus the addition of urea. Grain sorghum silage tannin content affects milk production, without significant alteration of chemical composition. Beside the …

Changes Of Forages Fed To Dairy Cows In The Whole Year In Taiwan, F. H. Hsu, C. H. Lu

IGC Proceedings (1977-2023)

Objectives of this study were to determine the kinds and the percents of forages fed to dairy cows in the whole year. Data were taken weekly by the dairy farmers for one year, including kinds and weights of forages fed to dairy cows, the heads of milking cows, dry cows and heifers. Dairy farmer A used napiergrass (Pennisetum purpureum) green chop 68.2%, napiergrass silage 15.3%, pangolagrass (Digitaria decumbens) hay 3.2% and imported bermudagrass (Cynodon dactylon) hay 13.3% to feed cows. Dairy farmer B fed cows with napiergrass green chop 65.1%, pangolagrass 13.0% and imported …

Comparative Growth Performance Of West African Dwarf Goat Supplemented With Calliandra Calothyrsus, Leucaena Leucocephala, Or Cotton Seed Cake In West Cameroon, E. Tedonkeng Pamo, G. D. Assontia, C. Njehoya

IGC Proceedings (1977-2023)

A comparative growth performance study of African Dwarf Goats supplemented with Calliandra calothyrsus, Leucaena leucocephala or cotton seed cake was carried out on farm around Dschang and in the University Experimental Farm. Goats between 12 and 16 months of age were divided into 4 groups of 11 goats each with one group kept as a control. The supplemented animals received respectively 390 g of L. leucocephala, 380 g of C. calothyrsus (fresh matter) and 88.8 g of cotton seed cake each, corresponding to 6 g of nitrogen per animal per day. The animals were weighed every 21 days …

Voluntary Intake Of Tanzania Grass (Panicum Maximum) Under Rotational Grazing By Lactating Cows, M. L. P. Lima, T. T. Berchielli, J. R. Nogueira, A. K. D. Salman, Ana C. Ruggieri, Paulo Roberto Leme, L. J. M. Aroeira, J. P. G. Soares

IGC Proceedings (1977-2023)

The study was conducted at Nucleo de Pesquisas Zootecnicas Nordeste of the Instituto de Zootecnia, Ribeirão Preto, SP, in a rotational grazing area of Tanzania grass (Panicum maximum), to estimate the dry matter intake by lactanting cows. The estimation of dry matter intake was calculated from the feces production estimated using extrusa Chromium-mordent and the in vitro digestibility of diet. The three treatments were crossbreed cows fed 3 kg.day^-1 of concentrate, crossbred cows without concentrate suplementation and pure Gir cows also without concentrate supplementation. The milk production was 11.98, 6.53 and 5.46 kg per cow per day, …

The Effect Of Browse Species When Fed As A Supplement To Low Quality Native Grass Hay On Animal Performance, A. Elgersma, J. F. Oerlemans, D. B. Coates

IGC Proceedings (1977-2023)

A pen trial was conducted to measure the impact of some browse species when fed as a supplement on the nitrogen (N) and dry matter intake of cattle receiving low quality native grass hay. There were 8 treatments consisting of a nil-supplement control treatment, a urea supplement control, a green oaten hay control and 5 treatment groups based on browse supplements (Albizia lebbeck, Carissa spp. and Bursaria spp.). Treatment effect on increased native pasture intake was related to the amount of supplementary nitrogen (N), such that there was a significant linear relationship between dry matter intake of native …

Effects Of Different Levels Of Energy Supplementation On Growth Of Grazing Holstein Heifers, L. P. Novaes, C. E. Polan

IGC Proceedings (1977-2023)

Growth of Holstein heifers was studied for 1987 grazing season to evaluate pasture-drylot systems for raising dairy replacements. Orchardgrass (Dactylis glomerata L), tall fescue (Festuca arundinacea Schreb), bluegrass (Poa pratensis L) and white (Trifolium repens L) and red clover (Trifolium pratense, L) were the principal components of the grass-legume mixture in six paddocks of 1.5 ha each. Carrying capacity was estimated at six animals/ha (3.1 animal units) and excess forage was harvested as hay to control forage growth and quality. Grazing days were 140 days. None or 2.0 kg/d …

Intake And Growth Of Steers Offered Different Allowances Of Autumn Grass And Concentrates, Edward G. O’Riordan, P. French, Padraig O’Kiely, A. P. Moloney

IGC Proceedings (1977-2023)

The aim of this experiment was to quantify the relationship between autumn grass supply and concentrate supplementation level on grass intake and animal performance. One hundred and ten continental steers (567kg) were assigned to ten treatments in a three grass allowances: (6, 12 and 18kg dry matter (DM) per head daily) by three concentrate levels: (0, 2.5 and 5kg/head/daily) factorial design with a positive control group offered concentrates ad-libitum. Grass allowance was offered daily and concentrates were fed individually. The experiment began on August 22 and all animals were slaughtered after a mean experimental period of 95 days. Grass …

Fatty Acid Composition And Eating Quality Of Muscle From Steers Offered Grazed Grass, Grass Silage Or Concentrate-Based Diets, A. P. Moloney, P. French

IGC Proceedings (1977-2023)

The effects of grazed grass, grass silage or concentrates on the eating quality and fatty acid composition of intra-muscular fat of steers fed to achieve similar carcass growth rates were investigated. Fifty steers were assigned to one of five dietary treatments. The experimental rations offered daily for 85 days pre-slaughter were (a) grass silage plus 4 kg concentrate, (b) 8 kg concentrate plus 1 kg hay, (c) 6 kg grazed grass dry matter (DM) plus 5 kg concentrate, (d) 12 kg grazed grass DM plus 2.5 kg concentrate or (e) 22 kg grazed grass DM. Decreasing the proportion of concentrate …

Supplementation Of Lactating Cows Grazing Stargrass (Cynodon Nlenfuensis Var. Nlenfuensis) With Conjugated Linoleic Acid: Effects On Persistency And Estimated Net Energy Balance, S. R. Medeiros, D. E. Oliveira, L. J. M. Aroeira, M. Mcguire, D. P. D. Lanna

IGC Proceedings (1977-2023)

Thirty crossbread cows grazed stargrass (Cynodon nlenfuensis var. nlenfuensis) receiving 4kg/d of a supplement formulated to provide 115% of metabolizable protein requirements from the 4^th to the 11^th week of lactation. The cows received either 150g/head/day of Megalac (Control) or 150g/head/day of a Ca-protected conjugated linoleic acid (CLA, Church & Dwight). Residual effects of treatment were evaluated in weeks 12^th and 13^th. Milk production increased in CLA treated cows (P< 0.05). CLA decreased milk fat content (P< 0.0001) and yield (P< 0.01). Protected CLA increased protein content (P< 0.01) and yield (P< 0.01). The CLA residual effect on milk fat ends within one week after withdrawal but the benefits on milk yield and total solids production continued, due to the increased persistency. The estimated energy balance and intake were not greatly affected by treatment, as treated cows had higher milk volume and had higher protein productions.