Sorghum-sudangrass Hybrid Research Articles

Cytogenetical Studies on Sorghum (<I>S. bicolor</I>), Sudangrass (<I>S. sudanense</I>), and Their Hybrid

Sudangrass (Sorghum sudanense) and sorghum (S. bicolor) are two members of the genus Sorghum (Gramineae). Their hybrids have exhibited favorable forage yields and overall improved quality and disease resistance. They are widely used in aquaculture, production of livestock food and environmental protection, but some disagreements exist as to whether they actually belong to the same species. The Karyotypes of two sudangrass varieties, two sorghum varieties, three sorghum-sudangrass F1 hybrids were analyzed by the method of cell wall degradation and hypotonic treatment for chromosome preparations, and the meiosis behavior of three F1 hybrids and the chromosome numbers of two F2 hybrids were observed. The result showed that the karyotypic types of sorghum and sudangrass were 1A, and the karyotype formula was 2n=18 m+2 sm (sat) for Sa, 2n=20m for 3042A and 3042A×Sa F1, and 2n=20m(sat) for the others. The difference of chromosomes among three groups (i.e. sudangrass, sorghum, and sorghum-sudangrass hybrid F1) were not significant in terms of absolute long arm, absolute short arm, absolute total length, arm ratio (l/s), relative total length (P＞0.05); the change of chromosome length was not obvious in sorghum and sudangrass. The paired chromosome configuration of sorghum-sudangrass hybrid F1 in pollen mother cells at diakinesis and metaphaselwas 2n=2x=20(10II) and the chromosome pairing behavior was regular, but the frequencies of rod bivalent of Tx623A×S722 F1, 3042A×Sa F1, and Tx623A×Sa F1 were 4.887, 5.710, and 5.126, respectively; those of ring bivalent were 5.113, 4.290, and 4.874, respectively. At anaphase I, the paired chromosomes of sorghum-sudangrass hybrid F1 could separate from each other. The chromosome numbers of F2 hybrid were 20 (2n=20). Therefore, the sudangrass/sorghum relationship is sufficiently close.

Seeding rate for the sorghum‐sudangrass hybrid (Sorghum bicolor Moench × Sorghum sudanense [Piper] Stapf.) in the mixed seeding cultivation with corn (Zea mays L.) under a partial tillage condition in Kyushu region, Japan

AbstractIn the Kyushu region of Japan, mixed seeding cultivation of corn and sorghum is promising as a labor‐saving cropping system that makes effective use of forage crop fields in the summer season. In this study, we tested a few levels of seeding rates of a sorghum‐sudangrass hybrid (SSH) in a mixed seeding with corn planted at the standard rate (6.67 plants m−2) under a partial tillage condition in fields where Italian ryegrass had been sown after manure application and its second crop had been harvested. Our results indicate that the appropriate seeding rate of SSH with corn under partial tillage to maximize both the corn yield in the first crop and the annual yield is 1 g m−2, irrespective of the manure application levels. At this rate, the annual yield from the mixed‐seeded plots of corn and SSH was 20% higher than that from plots on which corn was seeded alone.

Nitrate‐Nitrogen Concentrations in the Perched Ground Water under Seepage‐Irrigated Potato Cropping Systems

Excessive nitrogen rates for potato production in northeast Florida have been declared as a potential source of nitrate pollution in the St. Johns River watershed. This 3-yr study examined the effect of N rates (0, 168, and 280 kg ha(-1)) split between planting and 40 d after planting on the NO(3)-N concentration in the perched ground water under potato (Solanum tuberosum cv. Atlantic) in rotation with sorghum sudan grass hybrid (Sorghum vulgare x Sorghum vulgare var. sudanese, cv. SX17), cowpea (Vigna unguiculata cv. Iron Clay), and greenbean (Phaseolus vulgare cv. Espada). Soil solution from the root zone and water from the perched ground water under potato were sampled periodically using lysimeters and wells, respectively. Fertilization at planting increased the NO(3)-N concentration in the perched ground water, but no effect of the legumes in rotation with potatoes on nitrate leaching was detected. Fertilization of green bean increased NO(3)-N concentration in the perched ground water under potato planted in the following season. The NO(3)-N concentration in the soil solution within the potato root zone followed a similar pattern to that of the perched ground water but with higher initial values. The NO(3)-N concentration in the perched ground water was proportional to the rainfall magnitude after potato planting. A significant increase in NO(3)-N concentration in the perched ground water under cowpea planted in summer after potato was detected for the side-dressing of 168 kg ha(-1) N applied to potato 40 d after planting but not at the 56 kg ha(-1) N side-dress. Elevation in NO(3)-N concentration in the perched ground water under sorghum was not significant, supporting its use as an effective N catch crop.

Effect of age of a sorghum-sudangrass hybrid on its allelopathic action

Hybrids of Sorghum sudanensis (sudangrass) and Sorghum bicolor genotypes can produce high amounts of biomass, sorgoleone (a long chain hydroquinone), and other phytotoxic substances. Shoots and roots of a sorghum-sudangrass hybrid (cv. Trudan 8) were collected 10, 20, 30, 40, and 50 days after emergence. Four concentrations of aqueous extracts from the shoots and roots (0, 0.4, 2, and 10 g L-1, w/v) were used to treat seeds of lettuce (Lactuca sativa), tomato (Lycopersicum sculentum), purslane (Portulaca oleracea), and pigweed (Amaranthus retroflexus). Seed germination of lettuce, tomato, and pigweed was inhibited by extracts from sorghum-sudangrass shoots at 10 g L-1 when made from sorghum-sudangrass plants 20 days or less in age. Seed germination of purslane was not inhibited by any sorghum-sudangrass extract. Growth of the four species evaluated were systematically inhibited when treated with 10 g L-1 extracts from sorghum-sudangrass shoots harvested up to 10 days after emergence.

Management of soil microbial communities to enhance populations of Fusarium graminearum-antagonists in soil

Fusarium head blight (FHB), incited by Fusarium graminearum Schwabe is one of the most devastating diseases of wheat. Primary inoculum generated on crop residue is the driving force of FHB epidemics. Fusarium survival on crop residues is affected by soil microbial antagonists. The incorporation of green manures has been shown to increase the density and diversity of microbes in soils, particularly the density and the pathogen-inhibitory activity of specific bacteria and fungi. Evidence of increased streptomycete populations in soil as a response to green manure incorporation, and their negative effect on the survival of Fusarium oxysporum Schlechtendahl in soil, suggests their potential use to reduce the survival of related pathogens. There is, however, no precedent for the use of green manures to promote indigenous streptomycete populations to control FHB. This study investigated the use of green manures (sorghum–sudangrass hybrid [Sorghum bicolor (L.) Moench–S. bicolor (L.) Moench var. sudanense (Piper)] and common buckwheat [Fagopyrum esculentum (Moench)]) for reducing F. graminearum survival in association with wheat residues. Soil bacterial density, streptomycete density and the density and inhibitory activity of F. graminearum-antagonists were monitored from planting until 3 and 6 months following the incorporation of green manures in greenhouse and field experiments, respectively. The decomposition of wheat residues and survival of Fusarium in residues was also assessed. The use of green manures did not statistically impact the survival of F. graminearum in wheat residue. However, green manures promoted the development of higher densities and antagonistic abilities of F. graminearum-antagonists in soils. Additionally, streptomycete densities and F. graminearum-antagonist densities were significantly and positively correlated with reduced survival of Fusarium. The results of our study suggest that the use of green manures can enhance populations of indigenous soil microorganisms antagonistic to the survival of F. graminearum in wheat residue.

Diversity comparison and phylogenetic relationships of S. bicolor and S. sudanense as revealed by SSR markers

Phylogenetic relationships among 48 accessions of sorghum ( Sorghum bicolor), sudangrass ( S. sudanense) and their relatives ( S. propinquum, S. halepense, Zea mexicana, Z. mays) were investigated using SSR markers. The 91 SSR primer pairs generated a total of 723 polymorphic alleles, with an average of 7.945 alleles per locus, and a range of 2–19 alleles. The average genetic diversity, as measured by the polymorphic information content (PIC), was 0.783. The average polymorphic rates were 84.530% and 78.483% within sorghum and sudangrass, respectively. The PIC values were 0.774 and 0.770, respectively, and there was no significant difference ( P > 0.05) between sorghum and sudangrass. Additionally, the genetic distance (GD sor–su) between sorghum and sudangrass was only 0.035, suggesting a high degree of genetic homogeneity. Genetic similarity (GS) values between all varieties ranged from 0.217 to 0.975 and were used to produce a dendrogram. The 48 accessions were clustered into five groups (GS = 0.766), specifically, group I (consisting of sorghum, sudangrass and sorghum–sudangrass hybrids), group II ( S. propinquum), group III ( S. halepense), group IV ( Z. mexicana) and group V ( Z. mays). Results of our analyses suggest the sudangrass/sorghum relationship is sufficiently close to place them both within the same species – sorghum ( S. bicolor).

논에서 수수 X 수단그라스 교잡종 재배시 가축분뇨 이용이 생육특성, 수량, 사료가치 및 NO3-N의 용탈에 미치는 영향

본 시험은 논에서 가축분뇨를 활용하여 수수<TEX>${\times}$</TEX>수단그라스 교잡종 재배시 생육특성, 수량 및 토양중의 질산태 질소의 변화를 구명하기 위하여 2003년부터 2005년까지 3년간 축산연구소(수원) 포장에서 시험을 실시하였으며 그 결과를 요약하면 다음과 같다. 수수<TEX>${\times}$</TEX>수단그라스 교잡종의 생육특성 중 초기생육은 화학비료구 4.3에 비하여 가축분뇨를 시용한 경우 <TEX>$2.5{\sim}3.8$</TEX>로 양호하였고 1차 예취후 재생은 화학비료구 3.0에 비하여 돈분액비, 발효돈분구는 각각 2.8로 양호한 반면 발효우분구는 4.1로 불량하였다. 가축분뇨별 시용수준 간에는 가축분뇨 100% +화학비료 25%> 가축분뇨 75%+화학비료 25%> 가축분뇨 100% 순으로 생육이 양호하였다. 건물수량은 화학비료에 비하여 돈분액비 23%, 발효돈분 18% 증수되었으나, 발효우분구는 12% 감소되었다. 또한 TDN 수량도 같은 경향으로 돈분액비 시용구에서 24%, 발효돈분 시용시에 18% 증가되었으며 발효우분의 경우는 12% 감소되었다. 사료가치는 가축분뇨를 시용함으로 조단백질 함량이 화학비료 시용구 5.9% 보다 다소 낮아지는 경향으로 돈분액비 5.6%, 발효돈분 5.4%, 발효우분 5.5%이었다. 가축분뇨의 시용방법 간에는 일정한 경향이 나타내지 않았다. RFV에 있어서도 화학비료구가 81로 가장 높았으며, 가축분뇨를 시용한 구에서는 다소 낮아지는 경향으로 돈분액비 77, 발효돈분 77, 발효우분 79 이었다. <TEX>$NO_{3^-}N$</TEX> 용탈량(2년 평균)은 평균 돈분액비구 <TEX>$37.0mg/{\ell}$</TEX>, 발효 돈분구 <TEX>$32.9mg/{\ell}$</TEX>으로 많았으며 발효우분구는 <TEX>$17mg/{\ell}$</TEX>으로 적었다. 가축분뇨 시용수준 간에는 가축분뇨 100%+화학비료 25%>가축분뇨 75%+ 화학비료 25%>가축분뇨 100% 순이었으며 가축분뇨의 종류에 관계없이 시용 초기에 용탈량이 많았다. The experimental work was conducted to determine the growth characteristics, yield and feed value of sorghum-sudangrass hybrid and <TEX>$NO_{3^-}N$</TEX> leaching by application of various types of livestock manure (LM) at National Livestock Research Institute, Suwon, for 3years (2003-3005). The growth characteristics in chemical fertilizer (CF) was better than others in general. The growth characteristic of sorghum-sudangrass hybrid by the various type of LM was good in order of composted swine manure (CSM) > liquid swine manure (LSM) > composted cattle manure (CSM), whereas the growth characteristics by application level of LM was good in order of LM 100%+CF 25%>LM 75%+CF 25%>LM 100%. Dry matter(DM) yield in LSM and CSM increased by 23% and 18% respectively while DM yield in CCM decreased 24% as compared to CF. Moreover total digestible nutrients (TDN) in LSM and CSM increased by 24% and 18% respectively while TDN in CCM decreased 12% as compared to CF. Crude protein and relative feed value in LM decreased compared to those in CF. <TEX>$NO_{3^-}N$</TEX> leaching by application level of LM showed that there was an increase in order of LM 100%+ CF 25%>LM 75%+CF 25%>LM 100%. Also the high concentration of <TEX>$NO_{3^-}N$</TEX> occurred shortly after application of LM.

Valor nutricional de híbridos de sorgo com capim-sudão em comparação ao de outros volumosos utilizados no período de baixa disponibilidade das pastagens

The objective of this study was to compare the nutritional value of sorghum-sudangrass hybrids to roughages collected in differed pastures, reserves of forage for using in cutting regime and conserved forage as hays or silages. The sorghum-sudangrass hybrids AG2501C and BRS800 showed similar bromatological composition and in vitro dry matter digestibility (IVDMD). Compared to other roughages, theses hybrids presented a higher protein level and intermediary values of cell wall contents. The coefficients of IVDMD observed for sorghum-sudangrass hybrids were not statistically different to the results of corn silage, elephantgrass and sugarcane managed in cutting regime. However, IVDMD of those hybrids was significantly higher than of coast-cross and tifton 85 hays, sorghum silage and differed pastures of Brachiaria brizantha and signal grass. The results indicated that sorghum-sudangrass hybrids may be used as roughage of high nutritional value during the drought.

Incinerated Sewage Sludge Products as Amendments for Agricultural Soils: Leaching and Plant Uptake of Trace Elements

Preliminary leaching column and greenhouse plant uptake studies were conducted in two soils with contrasting characteristics amended with varying rates (0 to 148.3 Mg ha−1) of incinerated sewage sludge (ISS) and weathered sewage sludge (WISS) to estimate the leaching losses of trace elements from the soils amended with incinerated sewage sludge by products and to evaluate the uptake and accumulation of these elements in various parts of Sorghum vulgaris var. sudanense Hitche. (“Sorgrass''), a Sorghum-Sudan grass hybrid. Results of this study indicated that leaching of Cr, Cd, Zn, Cu, Ni, Fe and Mn from soils amended with ISS and WISS increased with increasing rates of amendment. Results of the leaching column study further revealed greater leaching losses from coarse-textured soil compared to medium-textured soil and also from ISS amended soils than with WISS amended soils. Results further suggested that the type of element and the interaction between the element and soil properties affected the leachability of various trace elements. The uptake study indicated uptake and accumulation of trace elements by plant parts increased with increasing rates of amendments. Greater plant uptake and accumulation of trace elements were observed in plant parts grown in soils amended with ISS compared to that of WISS. Results also indicated a greater accumulation of trace elements in below ground part of the plants (roots) compared to that was observed in above ground parts (shoots). Limited data obtained from this one season preliminary studies demonstrated that incinerated sewage sludge products from wastewater treatment plants could be used as soil amendments at low application (no more than 24.7 Mg ha−1) for optimum plant growth, and dry matter yield without resulting in substantial accumulation of metals in plant parts at concentrations above the recommended critical limits and without causing significant leaching losses of various trace elements. It is imperative that long-term field studies are necessary to evaluate the long-term impact of using these new products in leaching and accumulation of various trace elements in plants and soils.

Yield of ‘Superior’ potatoes (Solanum tuberosum) and dynamics of root-lesion nematode (Pratylenchus penetrans) populations following “nematode suppressive” cover crops and fumigation

Studies were conducted at Simcoe, Ontario from 1992 to 1996 to evaluate various cover crop species as possible alternatives to fumigation prior to potatoes (Solanum tuberosum). Cereal rye (Secale cereale), a common overwinter cover crop in vegetable production systems, is an excellent host for the root-lesion nematode (Pratylenchus penetrans) and provides a suitable overwintering host on coarse sandy soils. Vorlex Plus CP and Telone IIB fumigants were compared to 'Domo' mustard (Brassica juncea) for the 1993 and 1994 potato crop years. Rye plus red clover (Trifolium pratense) was included as a known host cover crop system. Cyanogenic plants including 'Domo' mustard (1994) or 'Cutlass' mustard (1995, 1996), 'Forge' canola (Brassica rapa), 'Sordan 79' and 'Trudan 8' sorghum-sudangrass hybrids (Sorghum bicolor), and flax (Linum usitatissimum) were compared to Vorlex Plus CP fumigant and 'NK557' sorghum (Sorghum vulgare) for effects on potato yield and nematodes. Shallow (15 cm) and deep (45 cm) fumigation with Vorlex Plus CP were also compared prior to potatoes for the 1994 to 1996 crop years. There was little detectable difference in percent or days to 50% emergence of potatoes following any treatment. Highest total and marketable yields resulted from Telone IIB fumigation, then Vorlex Plus CP fumigation and 'Domo' mustard, followed by control and rye plus red clover cover. Populations of nematodes surpassed the threshold of 1000 kg-1 soil in all treatments and were highest in potatoes following rye plus red clover. Yield and nematode control following sorghum-sudangrass hybrids and mustards appeared to be intermediate between fumigated and not fumigated. All of the cover crops appeared to be root-lesion nematode hosts in the field, and reduction of population levels appeared to result after incorporation or nematode winterkill. Nematode mortality was excellent with fumigation and next best from kill over the winter after 'Sordan 79' incorporation. 'Sordan 79' grown over at least part of the summer followed by incorporation was an alternative to fumigation prior to potatoes. Deep chiselling appears to reduce nematode population, possibly by physical action. Where nematode populations warrant, deep fumigation prior to potatoes appears to be of merit.

Laboratory and Greenhouse Evaluation of Quicklime Sources for Suitability as Agricultural Liming Materials

Quicklime or burnt lime (CaO), is a highly soluble liming material recognized as an acceptable means for neutralization of acid soils in the United States. Blending CaO and MgO with agricultural lime (CaCO3) may prove an alternative to ground agricultural limestone for raising soil pH and providing fertilizer Ca and Mg for crop growth. The objectives of this study were to determine the chemical properties of several CaO, MgO, and CaCO3 liming blends compared to carbonate limestones, and analyze their respective effects on soil solution chemistry and shoot yield of a sorghum-sudangrass hybrid grown under greenhouse conditions. Three formulations of oxide liming materials (CaO, CaO + CaCO3, and CaO + MgO + CaCO3) were evaluated in the laboratory to determine their respective effectiveness as soil amendments compared to two dolomitic limestones (ground and pelletized) and reagent-grade calcium hydroxide [Ca(OH)2]. A 150-day incubation study was conducted to determine the effects of liming materials on soil pH and extractable nutrients, and a greenhouse study was completed to observe the effects of liming materials and rates on the herbage yield of a sorghum-sudangrass hybrid. Oxide liming materials averaged higher calcium carbonate equivalence (CCE) than ground and pelletized dolomitic limestones. An incubation study found CaO, CaO + CaCO3, and CaO + MgO + CaCO3 resulted in rapid pH adjustments (from pH 4.1 and 4.4 to 6.0 +) at one day after test initiation for two soil types and gave higher mean pH values than carbonate limes when applied at equivalent rates based upon CCE. Oxide liming materials also resulted in higher concentrations of soil extractable calcium (Ca) and magnesium (Mg), and the use of all liming materials, regardless of chemical form, alleviated Al toxicity. In a nine week greenhouse bioassay, all oxide liming materials and reagent-grade Ca(OH)2 were applied at 1/2X, 1X, and 2X the recommended application rate of ground dolomitic limestone based on CCE, resulting in similar or higher shoot yields comparatively at conclusion of this study. Because oxide liming materials have higher CCE values and provide more water-soluble sources of fertilizer Ca and Mg compared to ground and pelletized limestone, producers have potential for obtaining a more complete neutralization of acid soil conditions and shoot yields similar to or higher than those obtained with dolomitic limestone, using less material in the process. This study did not determine if changes in current liming practices would result in reductions of total fertilizer costs per year using oxide limes in place of carbonate forms.

Trends in Forage Yield and Nutritive Value of Hay‐Type Sorghum spp.

Sudangrass [Sorghum bicolor (L.) Moench], other Sorghum spp., and sorghum–sudangrass hybrids are used extensively for hay on U.S. cropland because of their production potential. Performance evaluations have emphasized yield and other agronomic characteristics but seldom emphasized forage quality. Available hay‐type sorghum cultivars released over a period of four decades were grown in five trials over a 21‐yr period to evaluate trends in forage yield and nutritive value. First‐cut (boot stage to head emergence) forage was harvested for yield and subsampled for one or more quality components. The first trial in 1977 tested forage crude protein (CP), and subsequent trials included more quality traits. In 1993 and 1998, the traits measured included leaf/stem ratio and leaf and stem concentrations of CP, neutral‐detergent fiber (NDF), and acid‐detergent fiber (ADF). Pearson correlation coefficients by year and correlations pooled across trials by two methods indicated similar relationships between forage characteristics and year of cultivar release. Year of release was positively associated with forage yield in two of the five trials and for the pooled correlations. Forage CP and CP of leaf and stem fractions were negatively correlated with year of cultivar release for the pooled trials and in most individual trials. Leaf NDF and ADF were positively correlated with year of cultivar release in the pooled trials. Yield gains of about 0.5% per year were found, but concomitant relative reductions of 0.1% or more per year in forage CP and leaf NDF run counter to the perceived need for improved hay quality. These findings emphasize the need to locate and incorporate cost‐effective sources of germplasm to enhance nutritive value of forage in hay‐type Sorghum spp.

Determination of Qualities of Corn, Sorghum, Sudangrass and Sorghum x Sudangrass Hybrid Silages

Bakıcı, Y. and Demirel, M. 2004. Determination of qualities of corn, sorghum, sudangrass and sorghum x sudangrass hybrid silages. J. Appl. Anim. Res., 26: 45–48. To determine the silage qualities plants of corn (C), sorghum (S), sudangrass (SU) and sorghum x sudangrass hybrid (SSUH) were harvested at milk stage and incubated in concrete silos for 70 days. The corn silage was superior to the other three silages in terms of lactic and butyric acid contents, digestibilities of proximate principles except CP, the other three generally not differing among themselves. All the four silages were of high quality in terms of physical properties and flieg points and these crops are recommended for silage making.

Effect of Nitrogen Rate and Stubble Height on Dry Matter Yield, Crude Protein Content and Crude Protein Yield of a Sorghum–Sudangrass Hybrid[Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) Stapf.] in the Three‐Cutting System

AbstractIn this study, the effects of nitrogen (N) rate (60, 120, 180 and 240 kg N ha−1 applied in three equal dressings at seeding and after the first and second cuttings) and stubble height (7, 14 and 21 cm) on the dry matter (DM) yield, crude protein (CP) content, and CP yield of a sorghum–sudangrass hybrid [Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) Stapf., cv. Pioneer 988] in the three‐cut system was investigated. The N rate had no significant effect in the first and third cuttings, but in the second cutting DM yields increased significantly with increase in N rate. The highest yield of 9.1 t ha−1 was obtained with 80 kg N ha−1 for the average of 2 years at the second cutting, but no significant difference was found among the 40, 60 and 80 kg N ha−1 rates. CP content and yield were not significantly affected by N rate at the first and third cuttings, but CP content and yield were significantly affected by application of N at the second cutting. Stubble height had a significant effect on CP content at the third cutting. However, it had no significant effect on CP content at the first and second cuttings. Stubble height had a significant effect on the CP yield at the first cutting, but no significant effect on CP yield at the second and third cuttings.

양마의 제주지역 지역 적응성, 생산성 및 사료가치에 관한 연구

본 시험은 제주지역에서 양마의 적응성과 생산량 및 사료가치를 구명하기 위해서 양마 Evergrlades 41, China Chong-pi 3 및 수수<TEX>$\times$</TEX>수단 교잡종 Pioneer 947를 이용하여 2000년 5월부터 11월까지 제주의 4개 지역( 제주시, 서귀포시, 성산 수산 및 한림 금악)에서 수행되었다. 건물수량은 수수<TEX>$\times$</TEX>수단 교잡종 (pioneer 947), 양마 (Everglades 41) 및 (China Chong-pi 3)을 비교시 각각 7,313, 4,653 및 5,238 kg/ha로서 Chong-pi 3이 가장 높은 수량을 보였고(P<0.05) 지역별(제주, 서귀, 성산 및 한림)로 각 각 5,040, 5,663, 7,283 및 4,950 kg/ha서 성산지역이 가장 높은 수량을 보였다(P<0.05). 양마 두 품종 모두에서 1회 수확이 2회 수확 보다 높은 건물수량을 보였다. NDF 및 ADF 함량은 두 양마 품종간 또는 수수X수단 교잡종과 양마간 뚜렷한 차이가 없었고 조단백질 함량은 수수<TEX>$\times$</TEX>수단 교잡종 Pioneer 947, 양마 Everglades 41 및 China Chong-pi 3에서 각각 12.60, 16.1 및 16.20%를 보여 수수<TEX>$\times$</TEX>수단 교잡종 보다 양마에서 높은 조단백질 함량을 보였으며(p<0.05) 지역 간에 차이가 분명치 않았다. 그러나 1회 예취(13.72%) 보다 2회 예취 시(17.75%) 양마의 조단백질 함량이 유의적으로 증가하였고(P<0.05) 한편 NDF(50.61, 42.57%)와 ADF(50.66, 41.61) 함량은 1회 보다 2회에서 유의적 감소를 보였다. (P<0.05). 수확이 끝난 후 수수<TEX>$\times$</TEX>수단 교잡종(Pioneer 947)과 양마 2 품종(Everglades 41, China-chong-pi 3)을 재배했던 4개 지역 토양에 대한 중금속 함량을 조사한 결과 처리간 뚜렷한 차이를 발견치 못했다. 결론적으로 양마는 수수<TEX>$\times$</TEX>수단 교잡종 보다 건물수량이 높지 못하였으나 조단백질 함량이 수수<TEX>$\times$</TEX>수단 교잡종 보다 높았고 그 중 1회 보다 2회 예취를 하므로 더 높은 조단백질 함량 을 보였다. A field trial was conducted from May to November 2000 at four regions of Jeju province(Jeju, Seogwipo, Susan Seongsan and Keumak Hallim) to estimate adaptation, dry matter yield and nutrient value of kenafs(Everglades 41 and China Choung-pi 3) and a sorghum-sudangrass hybrid(Pioneer 947). Total dry matter(DM) yields of sorghum-sudangrass hybrid Pioneer 947, kenaf Everglades 41 and kenaf China Chong-pi 3 were 7,313, 4,653 and 5,238 kg/ha(P<0.05), respectively, kenaf China Chong-pi 3 being the highest. The region specific dry matter(DM) yields of Jeju, Seogwipo, Seongsan and Hallim area were 5,040, 5,663, 7,283 and 4,950kg/ha, respectively, showing that Seogwipo was the highest. Average DM yields of two kenaf varieties were 4,946, and 3,246 kg/ha for 1st time-cutting and 2nd time-cutting, respectively. The average dry matter(DM) yield of kenaf was significantly higher in the 1st time-cutting than the 2nd time. No significant difference in neutral detergent fiber(NDF) and acid detergent fiber(ADF) contents was found among three varieties. The average crude protein(CP) content of kenaf was higher than that of sorghum-sudangrass hybrid(P<0.05) and was higher in 2nd time-cutting than in 1st time-cutting(P<0.05). There were no significant difference in the heavy metal content of soil either between the sorghum hybrid and kenafs or between two kenaf varieties. In conclusion, the average dry matter(DM) yield of kenaf was lower than that of sorghum hybrid, Contrarily the crude protein(CP) content of kenafs was higher than that of the sorghum hybrid. The average dry matter(DM) yield of kenaf showed higher in 1st time-cutting than 2nd time-cutting, while the crude protein(CP) content of kenafs decreased with time.

Effect of Nitrogen Rates and Method of Nitrogen Application on Dry Matter Yield and some Characters of Sorghum-Sudangrass Hybrid

In this study, the effect of nitrogen (N) rates (0, 40, 80, 120, 160 and 200 kg N ha -1 ) and methods of N application (A 1 : all N at sowing; A 2 : no N at sowing, half N after the first cutting and the remaining half after the second cutting; A 3 : one-third N at sowing, one-third after the first cutting, and the last third after the second cutting) on dry matter (DM) yield and some characters of the sorghum-sudangrass hybrid was investigated. DM yield increased significantly from 27.0 g pot -1 (0 kg N ha -1 ) to 38.6 g pot -1 (120 kg N ha -1 ). Higher N rates continued to increase the number of tillers per plant -1 (except for 40 and 80 kg N ha -1 ). N rates have significant effect on crude protein (CP) content, and CP content varied from 6.71 to 7.08%. N up to 120 kg N ha -1 rate increased CP yield, but no difference was observed among 80, 120, 160 and 200 kg N ha -1 . There was no significant effect of the method of N application in terms of DM yield, tillering and CP yield. However, the method of N application had a significant effect on CP content, which was 7.09% by A 1 , 6.97% by A 2 and 6.57% by A 3 .

Comparative Evaluations of Rice and a sorghum–sudangrass Hybrid as Crawfish Forage Crops

Abstract Comparisons were made among experimental ponds of red swamp crawfish Procambarus clarkii that were planted with either rice Oryza sativa, a sorghum–sudangrass hybrid Sorghum bicolor × S. sudanense, or a mixture of rice and sorghum–sudangrass. sorghum–sudangrass produced the greatest forage biomass and also exhibited the best biomass persistence. Ponds planted in rice, the industry standard, had the highest dissolved oxygen, but were depleted of forage by the end of the production season. The rice and sorghum–sudangrass mixture maintained an intermediate profile of standing forage over the crawfish production season and exhibited the lowest dissolved oxygen values. Crawfish production was similar among all treatments and averaged 1,185; 1,135; and 1,107 kg/ha for ponds planted in rice, sorghum–sudangrass, and the rice and sorghum–sudangrass mixture, respectively. Size grade distributions of harvested crawfish were also similar. Crawfish growth trials conducted in enclosures placed over forage subs...

Herbicides with Crop Competition Replace Endophytic Tall Fescue (Festuca arundinacea)

Herbicides and interim summer crop treatments were studied in 1984 to 1987 to replace fungal endophyte-infected with endophyte-free tall fescue or red clover to improve forage quality. Foliar glyphosate or paraquat were applied in spring across interim crops with PRE herbicides. The interim crops, grain sorghum with atrazine, sorghum-sudangrass hybrid with metribuzin, or soybean with imazaquin, were each applied as confounded treatments across glyphosate or paraquat. Within an interim crop system, a follow-up glyphosate treatment was serially applied the next fall or spring. Then either red clover or endophyte-free tall fescue was spring drilled within the fall or spring glyphosate follow-up treatments. Glyphosate controlled old tall fescue better than paraquat, and improved the stand of the endophyte-free tall fescue. Control of tall fescue was 97% from 1.7 kg ai/ha glyphosate. Glyphosate reduced the endophyte from a 77% original infection level to 20% over all interim crops after drilling the endophyte-free tall fescue. Among interim crops, grain sorghum or the sorghum-sudangrass hybrid was more competitive than soybean with the uncontrolled tall fescue. Replacement with endophyte-free tall fescue was best in grain sorghum or sorghum-sudangrass hybrid stubble the next spring. Grain sorghum or sorghum-sudangrass hybrid following foliar glyphosate or paraquat treatment of endophyte-infected tall fescue reduced endophyte infection level in tall fescue to 28%. A follow-up fall treatment with glyphosate controlled tall fescue better than the spring retreatment and red clover and endophyte-free tall fescue were established better from fall retreated glyphosate. Red clover was easily established by drilling into the sod after treating endophyte-infected tall fescue with either glyphosate or paraquat.

A mycorrhizal pathogen ( Glomus macrocarpum Tul. & Tul.) of tobacco: effects of long- and short-term cropping on the mycorrhizal fungal community and stunt disease

A crop rotation experiment was conducted on two adjacent tracts of land differing in long-term croppin history (30 year in tall fescue pasture or 3 year in sorghum-sudangrass hybrid (SSGH).. Short-term crops were 2 years in tobacco or low-endophyte ( Acremonium coenophialum Morgan-Jones & Gams) tall fescue. Tobacco was grown on all plots in Year 3, and data relating mycorrhizal stunt disease of tobacco and populations of the stunt pathogen, Glomus macrocarpum Tul. & Tul., and of other members of the mycorrhizal fungal community, were taken. Disease incidence was highest with SSGH-tobacco and lowest with fescue-fescue, the other two combinations being intermediate. Mycorrhizal colonization was related to disease occurence. At the beginning of the season, populations of G. macrocarpum were equally high in land with a long-term history of SSGH, regardless of its short-term history; but at the end of the season, populations of G. macrocarpum among the four treatments were proportional to the incidence of disease. Populations of four mycorrhizal fungal species which were high in land with a short-term history of fescue were depressed by production of tobacco. Monocropping of tobacco appeared to narrow the diversity of the mycorrhizal fungal community and increased the proportion which is pathogenic, the overall result being lower productivity of soil for tobacco. Crop rotation of tobacco with fescue decreased the proportion of the mycorrhizal fungal community which is pathogenic and maintained productivity of soil for tobacco.

Influence of boron concentrations on some meta‐bolites of date palm and sorghum seedlings

Abstract Date palm (Phoenix dactylifera L. cv Khedhri) and sorghum (sorghum Sudan grass hybrid cv sugar Graze 11) plants were grown in vermiculite in a controlled environment and watered with a nutrient solution containing eight different concentrations of boron (B) (0 to 500 ppm), six months for date palm and four weeks for sorghum. The chlorophyll (Chl) content of the seedlings increased significantly with low concentrations of B for both date palm and sorghum, but no further significant increases were observed at higher concentrations. Generally, there was a positive correlation between B and calcium (Ca) content in the tissues of both seedlings when B concentrations were increased in the media. A negative correlation was found between B concentration in the media and the tissue content of phenolic compounds and the activity of some enzymes, such as polyphenol oxidase, IAA‐oxidase and phenylalanine ammonia‐lyase in the tissue, while there was a positive correlation in the case of peroxidase. Ribonuclei...