scholarly journals Diversity of Pathogenic Fungi on Plantation Forests of North and North-West Ethiopia

2017 ◽  
Vol 6 (2) ◽  
pp. 27-34
Author(s):  
Wendu A. Darge
Keyword(s):  
Leaf Spot ◽  
Pathogenic Fungi ◽  
Stem Canker ◽  
Pathogenicity Test ◽  
Survey Period ◽  
Management Options ◽  
North West ◽  
Plantation Forests ◽  
Fungal Isolates ◽  
Alternaria Species

Forest plantations in Ethiopia are mainly exotic genera of Eucalyptus, Cupressus, Casuarina, Pinus and native Juniperus species. Plantations species have suffered at varying degrees of attack by disease causing agents, particularly Amhara region is among regions with plantation forests that have in recent years been subjected to attack by diseases in Ethiopia. Plantation trees in commercial stands, farmlands and woodlots were surveyed for diseases symptoms in 20 selected areas of Amhara and Tigray from May to June 2016.Leaf blight, leaf spot, tip blight and stem canker were the most common symptoms appeared during the survey period with leaf spot and stem canker the most prevalent. Tree samples showing clear disease symptoms were collected, surface sterilized, cultured and morphologically characterized for pathogen identification.  A total of 42 isolates of fungi colonies were identified from samples collected of 20 localities. Morphological characterization of fungal isolates reveals, six fungal genera belonging to Alternaria, Dioplodia, Pestalotiopsis, Curvularia, Phoma, and Penicillium were the cause of the symptoms of the symptoms of the observed disease. Among the isolates 14 (33.3%) were Alternaria species, 15(37.7%) were Phoma species, and the remaining 13 isolates were Diplodia3(7.2%), Pestalopsis7(16.7%), Curvularia2(4.7%) and Penicillium1 (2. 4%).Based on the findings of the study Phoma lingam, Phoma glomerata, Alternaria alternata, genera of Curvularia, Pestalotiopsis, Penicillium, and Diplodia were found to be the cause of diseases of the tree plantations. Phoma and Alternaria species were the most prevalent isolates, showing a majority of symptoms observed on plantations were due to their co-infection. The pathogenicity test result of the research also confirms fungal isolates were the cause of the symptoms of the disease observed. The findings of this research enable to study and design appropriate management options for the future prevention and control of the diseases especially when there is prolonged environmental stress in the country.

scholarly journals Leaf Spot and Stem Blight Caused by Botrytis cinerea on Poinsettia in Argentina

Plant Disease ◽  
2005 ◽  
Vol 89 (12) ◽  
pp. 1359-1359
Author(s):  
H. E. Palmucci ◽  
P. E. Grijalba
Keyword(s):  
Botrytis Cinerea ◽  
Leaf Spot ◽  
Buenos Aires ◽  
Pathogenic Fungi ◽  
Pathogenicity Test ◽  
Euphorbia Pulcherrima ◽  
Conidial Suspension ◽  
Stem Blight ◽  
Potted Plants ◽  
Leaf Spots

Poinsettia (Euphorbia pulcherrima Will. ex. Klotzsch) is a worldwide potted or landscape ornamental plant that belongs to the Euphorbiaceae family. During 2003 and 2004, several symptoms were observed on poinsettia potted plants in nurseries and crops near Buenos Aires. Symptoms included irregular, brown, water-soaked spots on adult plants and leaf spots that extended causing stem blight in seedlings. Small pieces of diseased tissues were surface disinfected for 2 min in 2% sodium hypochlorite, plated on 2% potato dextrose agar (PDA), and incubated at 22°C for 48 h. Dense, whitish mycelia developed on PDA and then turned gray when asexual structures were formed. The fungus conidia were ellipsoid, hyaline, nonseptate, and were formed on botryose heads. The pathogenicity test was carried out on 10 plants using a conidial suspension (2 × 106 spores per ml) that was sprayed on leaves with and without injuries. All plants were incubated in a moist chamber at 22 ± 2°C for 48 h and then maintained in a greenhouse. After 3 days, symptoms similar to the original were observed on the inoculated plants. Control plants sprayed with distilled water remained symptomless. Koch's postulates were confirmed by reisolating the same fungus from diseased plants. In accordance with conidial and cultural characteristics, the pathogen was identified as Botrytis cinerea Pers: Fr. (1). To our knowledge, this is the first report of B. cinerea causing leaf spot and stem rot on poinsettia in Buenos Aires, Argentina. Reference: (1) M. V. Ellis and J. M. Waller. No. 431 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1974.

scholarly journals Characterization of Alternaria Species Associated with Leaf Spot Disease of Armoracia rusticana in Serbia

Plant Disease ◽  
2020 ◽  
Vol 104 (5) ◽  
pp. 1378-1389
Author(s):  
Jovana Blagojević ◽  
Jelena Vukojević ◽  
Borko Ivanović ◽  
Žarko Ivanović
Keyword(s):  
Leaf Spot ◽  
Leaf Age ◽  
Distinct Species ◽  
Host Susceptibility ◽  
Leaf Spot Disease ◽  
Pathogenicity Test ◽  
Armoracia Rusticana ◽  
Spot Disease ◽  
Haplotype Networks ◽  
Alternaria Species

Leaf spot diseases caused by Alternaria species have been reported worldwide in plants in the Brassicaceae family. However, there is little information on Alternaria species causing diseases in horseradish. In the present study, 89 Alternaria spp. isolates from Armoracia rusticana, sampled from nine districts in Serbia, were characterized based on their morphology, physiology, and molecular markers. Morphological characterization and molecular analyses based on ITS, GAPDH, Alt a 1, and PM-ATP sequences identified three distinct species associated with the disease: Alternaria brassicae, A. brassicicola, and A. alternata. For all species, growth and sporulation rates at 0, 5, 10, 15, 20, 25, 30, 35, and 40°C showed a quadratic response, with A. alternata having the widest temperature optimum (20 to 30°C) while A. brassicicola had higher optimum temperatures (20 to 25°C) than A. brassicae (15 to 20°C). To gain a better understanding of the pathogenicity of these species, the influence of leaf age, host susceptibility, and ability to infect artificially wounded and nonwounded leaves were tested. The pathogenicity test identified A. brassicicola and A. brassicae as the main causal agents of horseradish leaf spot disease. Results indicated that young and intact leaves of horseradish and cabbage were less susceptible to infection and also suggested the potential for cross-infection between these two hosts. Haplotype networks showed haplotype uniformity for A. brassicae, two haplotype groups of A. brassicicola, and eight haplotype groups of A. alternata in Serbia and suggest the possible association of some haplotypes with the geographic area. This study is the first to investigate Alternaria leaf spot disease on A. rusticana in Serbia and is the first record of A. brassicicola on horseradish in this country.

scholarly journals Alternaria Leaf Spot Caused by Alternaria Species: An Emerging Problem on Ornamental Plants in Italy

Plant Disease ◽  
2020 ◽  
Vol 104 (8) ◽  
pp. 2275-2287
Author(s):  
Slavica Matić ◽  
Giulia Tabone ◽  
Angelo Garibaldi ◽  
Maria Lodovica Gullino
Keyword(s):  
Leaf Spot ◽  
Ornamental Plants ◽  
Infected Plant ◽  
Haplotype Diversity ◽  
Population Expansion ◽  
Seed Transmission ◽  
Host Specialization ◽  
Alternaria Leaf Spot ◽  
Fungal Isolates ◽  
Alternaria Species

Serious outbreaks of Alternaria leaf spot and plant decay have recently been recorded on several ornamental plants in the Biella Province (Northern Italy). Twenty-two fungal isolates were obtained from Alternaria infected plant tissues from 13 ornamental hosts. All the isolates were identified morphologically as small-spored Alternaria species. Multilocus sequence typing, carried out by means of ITS, rpb2, tef1, endoPG, Alt a 1, and OPA10-2, assigned 19 isolates as Alternaria alternata, two isolates as belonging to the Alternaria arborescens species complex, and one isolate as an unknown Alternaria sp. Haplotype analyses of ornamental and reference A. alternata isolates from 12 countries identified 14 OPA10-2 and 11 endoPG haplotypes showing a relatively high haplotype diversity. A lack of host specialization or geographic distribution was observed. The host range of the studied A. alternata isolates expanded in cross-pathogenicity assays, and more aggressiveness was frequently observed on the experimental plants than on the host plants from which the fungal isolates were originally isolated. High disease severity, population expansion, intraspecies diversity, and increased range of experimental hosts were seen in the emergence of Alternaria disease on ornamentals. More epidemiological and molecular studies should be performed to better understand these diseases, taking into consideration factors such as seed transmission and ongoing climate changes.

scholarly journals First Report of Corynespora Leaf Spot of Eucalyptus in China

Plant Disease ◽  
2015 ◽  
Vol 99 (3) ◽  
pp. 419-419 ◽  
Author(s):  
C. K. Phan ◽  
J. G. Wei ◽  
F. Liu ◽  
B. S. Chen ◽  
J. T. Luo ◽  
...  
Keyword(s):  
Leaf Spot ◽  
Southern China ◽  
Tap Water ◽  
Pathogenic Fungi ◽  
Leaf Spot Disease ◽  
Pathogenicity Test ◽  
Commonwealth Mycological Institute ◽  
Conidial Suspension ◽  
Single Spore ◽  
First Report

Eucalyptus is widely planted in the tropics and subtropics, and it has become an important cash crop in Southern China because of its fast-growing nature. In the Guangxi Province of southern China, Eucalyptus is produced on approximately 2 million ha, and two dominant asexual clones, Guanglin No. 9 (E. grandis × E. urophylla) and DH3229 (E. urophylla × E. grandis), are grown. Diseases are an increasing threat to Eucalyptus production in Guangxi since vast areas are monocultured with this plant. In June 2013, a leaf spot disease was observed in eight out of 14 regions in the province on a total of approximately 0.08 million ha of Eucalyptus. Initially, the lesions appeared as water-soaked dots on leaves, which then became circular or irregular shaped with central gray-brown necrotic lesions and dark red-brown margins. The size of leaf spots ranged between 1 and 3 mm in diameter. The main vein or small veins adjacent to the spots were dark. The lesions expanded rapidly during rainy days, producing reproductive structures. In severe cases, the spots coalesced and formed large irregular necrotic areas followed by defoliation. The causal fungus was isolated from diseased leaves. Briefly, the affected leaves were washed with running tap water, sterilized with 75% ethanol (30 s) and 0.1% mercuric dichloride (3 min), and then rinsed three times with sterilized water. Small segments (0.5 to 0.6 cm2) were cut from the leading edge of the lesions and plated on PDA. The plates were incubated at 25°C for 7 to 10 days. When mycelial growth and spores were observed, a single-spore culture was placed on PDA and grown in the dark at 25°C for 10 days. A pathogenicity test was done by spraying a conidial suspension (5 × 105 conidia ml–1) of isolated fungus onto 30 3-month-old leaves of Guanglin No. 9 seedlings. The plants were covered with plain plastic sheets for 7 days to keep the humidity high. Lesions similar to those observed in the forests were observed on the inoculated leaves 7 to 10 days after incubation. The same fungus was re-isolated. Leaves of control plants (sprayed with sterilized water) were disease free. Conidiophores of the fungus were straight to slightly curved, erect, unbranched, septate, and pale to light brown. Conidia were formed in chains or singly with 4 to 15 pseudosepta, which were oblong oval to cylindrical, subhyaline to pale olivaceous brown, straight to curved, 14.5 to 92.3 μm long, and 3.5 to 7.1 μm wide. The fungus was morphologically identified as Corynespora cassiicola (1). DNA of the isolate was extracted, and the internal transcribed spacer (ITS) region (which included ITS 1, 5.8S rDNA gene of rDNA, and ITS 2) was amplified with primers ITS5 and ITS4. 529 base pair (bp) of PCR product was obtained and sequenced. The sequence was compared by BLAST search to the GenBank database and showed 99% similarity to C. cassiicola (Accession No. JX087447). Our sequence was deposited into GenBank (KF669890). The biological characters of the fungus were tested. Its minimum and maximum growth temperatures on PDA were 7 and 37°C with an optimum range of 25 to 30°C. At 25°C in 100% humidity, 90% of conidia germinated after 20 h. The optimum pH for germination was 5 to 8, and the lethal temperature of conidia was 55°C. C. cassiicola has been reported causing leaf blight on Eucalyptus in India and Brazil (2,3) and causing leaf spot on Akebia trifoliate in Guangxi (4). This is the first report of this disease on Eucalyptus in China. References: (1) M. B. Ellis and P. Holliday. CMI Descriptions of Pathogenic Fungi and Bacteria, No. 303. Commonwealth Mycological Institute, Kew, Surrey, UK, 1971. (2) B. P. Reis, et al. New Dis. Rep. 29:7, 2014. (3) K. I. Wilson and L. R. Devi. Ind. Phytopathol. 19:393, 1966. (4) Y. F. Ye et al. Plant Dis. 97:1659, 2013.

scholarly journals First Report of Lasiodiplodia theobromae Causing Needle Blight and Stem Canker Diseases on Araucaria heterophylla in Ethiopia

2017 ◽  
Vol 25 (2) ◽  
pp. 15-18 ◽  
Author(s):  
Wendu Admasu Darge
Keyword(s):  
Fungal Pathogens ◽  
Addis Ababa ◽  
Stem Canker ◽  
Pathogenicity Test ◽  
Management Options ◽  
Lasiodiplodia Theobromae ◽  
Araucaria Heterophylla ◽  
Pine Trees ◽  
Norfolk Island ◽  
Needle Blight

Abstract Canker and needle blight of Araucaria heterophylla (Norfolk Island pine) trees were observed during the surveys conducted in Addis Ababa and Adama cities (Ethiopia) from November to December 2016. The main objective of this study was to investigate fungal pathogens that cause diseases on Araucaria heterophylla trees. Six localities with Araucaria heterophylla plantings were purposively surveyed for disease symptoms. Samples from symptomatic parts of trees were collected, surface sterilized, cultured on PDA and morphologically identified for genus and species. A total of 36 isolates of fungi were identified. Based on macro- and microscopic morphological features of the colonies, the fungal isolates were found to be the genus Diplodia and species Lasiodiplodia theobromae (Pat.) Griffon & Maubl (syn. Botryodiplodia theobromae), the anamorph of Botryosphaeria rhodina (Berk. & M.A. Curtis) Arx. The pathogenicity test showed that the isolates of Lasiodiplodia theobromae, caused stem canker and needle blight on Araucaria heterophylla. This finding is important in the study of management options for future prevention and control of diseases in the country.

scholarly journals Isolation and Diagnosis of Pathogenic Fungi Associated With Zucchini Cucurbita Pepo Roots and Their Bio-Control

2021 ◽  
Vol 923 (1) ◽  
pp. 012014
Author(s):  
Muhsen Abd Ali ◽  
Nazar Rashid Merzah ◽  
Ali Faraj Jubair
Keyword(s):  
Germination Rate ◽  
Pathogenic Fungi ◽  
High Rate ◽  
Control Treatment ◽  
Pathogenicity Test ◽  
Dual Culture ◽  
Fresh Weight ◽  
Laboratory Conditions ◽  
Fungal Isolates ◽  
Plant Length

Abstract This study aimed to isolate and diagnose the main pathogens of zucchini root rot, test their pathogenicity, and evaluate their control with some biological agents under laboratory conditions. The results of diagnostic isolation from the roots of the zucchini crop that showed symptoms of the disease showed the presence and dominance of two isolates of Fusarium oxysporum (FO1, FO2), three isolates of Fusarium solani (FS1, FS2, FS3) and three isolates of Rhizoctonia solani (RS1, RS2, RS3) and two isolates of Pythium spp (PY1, PY2), which was present in a ratio of 65-25% in most of the samples collected from the fields of the Faculty of Agriculture/University of Karbala. F. solani had the highest frequency, at 60.00%, and had the highest occurrence in sample 3, which was 65.00%, followed by R. solani and F. oxysporum with 48.33 and 40.00% occurrence, respectively. The pathogenicity test of fungal isolates on red radish seeds showed that all isolates significantly reduced radish seeds germination under laboratory conditions. The results showed the effect of pathogenic fungal isolates on germination and growth of zucchini plants in protected cultivation, which led to a significant reduction in germination percentage, fresh weight of the plant, plant height and a high rate of disease severity. FS1 and RS1 isolates completely prevented seed germination, followed by FS2 and FO2 isolates with equal germination rate of 22.22%, compared to control treatment with 100% germination rate. FS2 isolate had the highest infection severity rate of 97%, followed by FO2 isolation with 94% compared to no infection in control treatment. The minimum plant length was 0.267 cm in the FS2 isolation treatment, followed by the FS3 isolate, with a plant length of 0.567 cm, compared to 2.553 cm in the control treatment. FO1 isolation led to the highest reduction in plant fresh weight by 81%, followed by isolate FS2 with 78% compared to control treatment. The test of the inhibitory ability of the biological control agents showed the presence of high antagonism of Trichoderma harzianum, Chaetomium sp and Sordaria sp against pathogenic fungal isolates. T. harzianum was the highest antagonistic against all the pathogenic fungal isolates, recording grade 1 antagonism according to Bell et al. (1982) after seven days of dual culture. Also, Chaetomium sp and Sordaria sp showed antagonistic ability of 1 and 2 degrees against pathogenic fungal isolates under study.

scholarly journals First Report of Alternaria alternata Causing Leaf Spot of Tartary Buckwheat (Fagopyrum tataricum) in China

Plant Disease ◽  
2021 ◽  
Author(s):  
Shaoqing Li ◽  
quan shen ◽  
Haihua Wang ◽  
Feng He ◽  
Zuyin Xiao ◽  
...  
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
Tartary Buckwheat ◽  
Pathogenicity Test ◽  
Conidial Suspension ◽  
Sterile Water ◽  
Fagopyrum Tataricum ◽  
First Report ◽  
Fungal Isolates ◽  
Initial Symptoms

Buckwheat (Fagopyrum tataricum) is recognized as a healthy food with abundant nutrients and high levels of rutin. In April and May of 2020, an unknown tartary buckwheat leaf spot distinct from Nigrospora leaf spot (Shen et al. 2020) was observed in Xiangxiang, Hunan, China (27°49′54″N, 112°span style="font-family:'Times New Roman'; color:#0000ff">18′48″E.). Disease incidence was 60-70% within three fields (totally 7, 000 m2). The disease occurred after plants emerged. Initial symptoms began as circular, or ellipsoid, chlorotic, water-soaked spots, mostly on leaf apexes or leaf margins. The small spots gradually enlarged and often coalesced to form large circular or irregular, pale to light brown lesions, and the infected leaves eventually withered and fell off. Thirty 2 × 2 mm infected tissue pieces collected from five locations were sterilized in 70% ethanol for 10 S, in 2% NaClO for 30 S, rinsed in sterile water for three times, dried, and placed on PDA with lactic acid (3 ml/L). After 3-5 days at 28°C in the dark, 17 fungal isolates were purified using single-spore isolation method. Almost all fungal isolates had similar morphology. Colonies were initially olive green with white margin and later turned dark olive or black with profuse sporulation. Conidia were borne in long chains, tawny to brownish green, with 1-3 longitudinal and 1-7 transverse septa, pyriform, and measured 9.5-39.6 µm long, and 5.1-12.6 µm wide (n=50). Based on morphological characteristics, the fungus was identified as Alternaria alternata (Simmons 2007). Partial internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), translation elongation factor 1-α(TEF) and Alternaria major allergen (Alt a1) genes of isolate BLS-1 were amplified using ITS1/ITS4 (Mills et al. 1992), EF1-728F/EF1-986R (Carbone and Kohn 1999), Gpd1/Gpd2 and Alt-4for/Alt-4rev (Lawrence et al. 2013), respectively. Sequences were deposited into GenBank with acc. nos MW453091 (ITS), MW480219 (GAPDH), MW480218 (TEF), and MW480220 (Alt a1). BLASTn analysis showed 99.8% (ITS, MH854758.1), 100% (GAPDH, KP124155.1), 99.8% (TEF, KP125073.1) and 100% (Alt a1, KP123847.1) identity with reference strain CBS 106.24 of A. alternata, confirming isolate BSL-1 to be A. alternata. A neighbor-joining phylogenetic tree constructed by MEGA7.0 based on concatenated sequences of the four genes indicated that BSL-1 formed a distinct clade with A. alternata CBS 106.24 with 100% bootstrap values. Pathogenicity test was triplicately performed on healthy leaves. Twenty leaves of five 20-day-old plants (cv. Pinku1) were sprayed with conidial suspension (1×106 conidia/ml) collected from PDA cultures with 0.05% Tween 20. An equal number of control leaves were sprayed with sterile water to serve as the controls. Treated plants were kept in a greenhouse at 28±3 °C with relative humidity of 80±5% for 24 h and transferred to natural conditions (22-30°C, RH 50-60%). After 4 to 6 days, all inoculated leaves developed symptoms similar to those observed in the fields, while the control leaves remained healthy. A. alternata was re-isolated from all infected leaves. Occasionally-isolated Diaporthe isolates were not pathogenic. A. alternata causes leaf spot of oat (Zhao et al. 2020) and leaf blight of F. esculentum (Lu et al. 2019). To our knowledge, this is the first report of A. alternata causing leaf spot on F. tataricum in China and the world. Effective strategies should be developed to manage the disease.

scholarly journals Using Commercial Compost as Control Measures against Cucumber Root-Rot Disease

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Kamel Kamal Sabet ◽  
Magdy Mohamed Saber ◽  
Mohamed Adel-Aziz El-Naggar ◽  
Nehal Samy El-Mougy ◽  
Hatem Mohamed El-Deeb ◽  
...  
Keyword(s):  
Root Rot ◽  
Control Measure ◽  
Disease Incidence ◽  
Pathogenic Fungi ◽  
Pythium Ultimum ◽  
Control Measures ◽  
Infested Soil ◽  
Fungal Isolates ◽  
Cucumber Root

Five commercial composts were evaluated to suppress the root-rot pathogens (Fusarium solani (Mart.) App. and Wr, Pythium ultimum Trow, Rhizoctonia solani Kuhn, and Sclerotium rolfsii Sacc.) of cucumber plants under in vitro and greenhouse conditions. In vitro tests showed that all tested unautoclaved and unfiltrated composts water extracts (CWEs) had inhibitor effect against pathogenic fungi, compared to autoclaved and filtrated ones. Also, the inhibitor effects of 40 bacteria and 15 fungi isolated from composts were tested against the mycelial growth of cucumber root-rot pathogens. Twenty two bacteria and twelve fungal isolates had antagonistic effect against root-rot pathogens. The antagonistic fungal isolates were identified as 6 isolates belong to the genus Aspergillus spp., 5 isolates belong to the genus Penicillium spp. and one isolate belong to the genus Chaetomium spp. Under greenhouse conditions, the obtained results in pot experiment using artificial infested soil with cucumber root-rot pathogens showed that the compost amended soil reduced the percentage of disease incidence, pathogenic fungi population, and improved the cucumber vegetative parameters as shoot length, root length, fresh weight, and dry weight. These results suggested that composts are consequently considered as control measure against cucumber root-rot pathogens.

Beef production from native pastures sown to fine-stem stylo in the Burnett region of south-eastern Queensland

1979 ◽  
Vol 19 (97) ◽  
pp. 140 ◽  
Author(s):  
EJ Bowen ◽  
KG Rickert
Keyword(s):  
Stocking Rate ◽  
Management Options ◽  
North West ◽  
Heteropogon Contortus ◽  
South Eastern ◽  
Continuous Grazing ◽  
Weight Gains ◽  
The Mean ◽  
Native Pastures ◽  
Stocking Rates

At Gayndah, south-eastern Queensland, a native Heteropogon contortus pasture, sown to fine-stem stylo (Stylosanthes guianensis var. intermedia), and invaded by red natal grass (Rhynchelytrum repens), was grazed by weaner steers from June 1 in three treatments : heavy and light put-and-take grazing for five years from 1971, and set-stocked at 1.37 animals ha-1 for two years from 1974. Weight gains in the put-and-take treatments were not significantly different. The mean annual liveweight gain was 167 kg animal-1 at a mean equivalent stocking rate of 1.47 animals ha-1. Over the same period unsown native pasture, cleared of timber, gave a gain of 62 kg animal-1 at 0.62 animals ha-1. In all seasons except summer, weight gains declined linearly with stocking rate and in 1972-73, with a mean equivalent stocking rate of 2.66 animals ha-1, the annual gain was almost halved. When equivalent stocking rates were 0.9, 0.9, 1.8 and 1.2 animals ha-1 in winter, spring, summer and autumn, the respective gains were 4, 73, 65 and 45 kg animal-1. The set-stocked treatment had a mean annual gain of 147 kg animal-1. At another site 116 km north-west of Gayndah, two paddocks of Heteropogon contortus and fine-stem stylo were set-stocked with weaners over four years. One paddock had four applications of superphosphate of 250 kg ha-1. The mean annual liveweight gains were significantly different, being 154 and 143 kg animal-1 in the fertilized and unfertilized paddocks at mean stocking rates of 0.83 and 0.74 animals ha-1, respectively. In a grazing protection experiment the density of fine-stem stylo declined exponentially with an accumulation of pasture dry matter in spring and summer. Heavy continuous grazing, an annual hay cut and an accidental fire all increased the density of fine-stem stylo. Management options to maintain the density of fine-stem stylo and the relative importance of the legume and grass to animal production are discussed.

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