Larval development and food habits of the marbled parrotfish, <Emphasis Type="Italic">Leptoscarus vaigiensis</Emphasis>, associated with drifting algae

The larval development and food habits of the marbled parrotfish, Leptoscarus vaigiensis (Scaridae) associated with drifting algae were studied. In this study, 628 L. vaigiensis of various developmental stages ranging from postflexion larvae (9.4mm in standard length, SL) to adults (192.0mmSL) were sampled from drifting algae at two fishing ports in Nakagusuku Bay of Okinawa Island. In 3969 fish comprising 65 taxa in 34 families of Teleostei collected with drifting algae, L. vaigiensis occupied 15.8% of samples and occurred generally throughout the whole year. A large number of L. vaigiensis were collected from July to October accompanied by an occurrence of drifting algae composed of Sargassum spp. Larvae and early juveniles ranging from 11.1 to 14.9mmSL appeared sporadically throughout the year, and postflexion larvae 11mmSL occurred from July to November. Their food shifted from planktonic copepods in postflexion larvae and juveniles ranging from 10.0 to 14.9mmSL to seaweed in the juveniles ranging from 15.0 to 24.9mmSL. Furthermore, adults and young over 25mmSL fed almost exclusively on seaweed, with Sargassum spp. constituting the drifting algae. These facts indicate that drifting algae may have a role concerning food and habitat, and may act as a nursery for L. vaigiensis.     

Fine root biomass,production and turnover in a fertilized <Emphasis Type="Italic">Larix leptolepis</Emphasis> plantation in central Korea

The effects of fertilization [control (C), 200kgNha^–1+25kgP ha^–1 (LNP) and 400kgNha^–1+ 50kgP ha^–1 (HNP)] on fine root dynamics were examined in a 40-year-old Larix leptolepis plantation in central Korea. The average fine root biomass during the growing season for C, LNP and HNP was 957, 934 and 814kgha^–1, respectively, whereas the fine root production for C, LNP and HNP was 2103, 2131 and 2066kgha^–1, respectively. Nitrogen and P inputs into the soil via fine root turnover for C, LNP and HNP were 23.0 and 1.2, 23.3 and 1.2 and 22.6 and 1.2kgha^–1, respectively. There were no significant differences in fine root biomass, production and N and P inputs through fine root turnover between the fertilization treatments during the first growing season after fertilization.     

Early development of the self-fertilizing mangrove killifish <Emphasis Type="Italic">Rivulus marmoratus</Emphasis> reared in the laboratory

The mangrove killifish Rivulus marmoratus was reared at 25°±1°C and 17ppt salinity from 0 to 100 days after hatching (DAH), and its early development was described by examining growth and morphometric parameters, meristic characters (vertebral and fin-ray counts), bone-cartilage development, and pigmentation. Growth was isometric for preanal length, head length, snout length, body depth, pectoral-fin length, dorsal-fin length, anal-fin length, and caudal-peduncle depth. Negative allometric growth was observed in eye diameter and gape size. Meristic counts (mean±SD) for vertebrae (34.2±0.4) and dorsal- (8.6±0.5), anal- (11.4±0.5), and caudal-fin rays (30.2±0.8) were complete at 0 DAH (n=5), whereas pectoral-fin rays and pelvic-fin rays were complete by 30 DAH (14.5±0.4, n=5) and 60 DAH (4.2±0.8, n=5). Full ossification of meristic elements proceeded in the following sequence: vertebrae (by 30 DAH), caudal-, dorsal-, and anal-fin rays (by 60 DAH), pectoral-fin rays (between 60 DAH and 100 DAH), and pelvic-fin rays (by 100 DAH). Both morphological characters and meristic counts indicate that this species can be considered to be a juvenile after 9.8mm in standard length (20 DAH).     

Biodegradation of bisphenol A by cells and cell lysate from <Emphasis Type="Italic">Sphingomonas </Emphasis>sp. strain AO1

The capacity and pathway of bisphenol A [BPA; 2,2-bis(4-hydroxyphenyl)propane] degradation in Sphingomonassp. strain AO1, which was isolated from the soil of a vegetable-growing field in Japan, were investigated. The bacterial strain was able to grow in a basal mineral salt medium containing BPA as the sole carbon source (BSMB medium), and was able to degrade 115 gml^–1 BPA in 6h in L medium. Several BPA metabolites were detected in the culture supernatant by HPLC and then identified by GC-MS and LC-MS-MS. These compounds were confirmed to be the same as those reported for other BPA-degrading bacteria. BPA degradation by cells in the basal mineral salt medium was induced by BPA, and activity was detected only in the intracellular soluble fraction in the presence of coenzymes, such as NADH, NAD⁺ , NADPH or NADP⁺. The addition of metyrapone, a cytochrome P450 inhibitor, to BSMB medium resulted in a decrease in BPA degradation and cell growth. The BPA-degradation activity of the intracellular soluble fraction was also inhibited by the cytochrome P450 inhibitor. Carbon monoxide difference spectra indicated that cytochrome P450 was present in the cells and that the amount of cytochrome P450 corresponded to the cellular BPA-degradation activity. Our results provide evidence that the cytochrome P450 system is involved in BPA metabolism in Sphingomonassp. strain AO1.     

<Emphasis Type="Italic">In vitro</Emphasis> screening of sugarcane to evaluate smut susceptibility

Tissue-cultured plantlets of three sugarcane (Saccharum spp.) cultivars having a known field smut reaction were screened for susceptibility to Ustilago scitaminea H&P Sydow. Plantlets were inoculated with 0.5 l of a suspension of equally mixed quantities of plus and minus mating type sporidia of U. scitaminea at concentrations ranging from 1×10¹ to 1×10⁶ cells. Fungal sori (whips) were produced in cultivar N12 (intermediate) 6weeks following inoculation with 1×10⁵ mixed sporidia and thereafter in cultivar NCo310 (susceptible) but not in cultivar N19 (resistant). Sori bearing teliospores were produced up to 3months following inoculation and incubation at 26°C. No sori were produced at mixed sporidial concentrations lower than 1×10⁵cells. The in vitro soral production in cultivars N19, N12 and NCo310 was 0, 27.5 and 47.5% respectively. Plantlets inoculated with 1×105sporidia of only one mating-type did not produce sori in any of the three cultivars tested. Blind scoring of an unknown sugarcane cultivar by this method corresponded exactly with its field smut rating.     

Mode of uptake of sterol by Arthrobacter simplex

The mechanism of uptake of water-insoluble -sitosterol by a newly isolated strain of Arthrobacter simplex SS-7 was studied. The production of an extracellular sterol-pseudosolubilizing protein during growth of A. simplex on -sitosterol was demonstrated by isolating the factor from the cell-free supernatant and its subsequent purification by Sephadex G-150 column chromatography. The M _r of the purified sterol-pseudosolubilizing protein determined by SDS–PAGE was 19kDa. The rate of sterol pseudosolubilization (5.2×10^–3g l^–1h^–1) could not adequately account for the rate of sterol uptake (72×10^–3g l^–1h^–1) and the specific growth rate (56×10^–3 h^–1). However in the unfavourable growth condition, when the cells were treated with sodium azide at the level of 30–60% of MIC, the sterol pseudosolubilization accounted for nearly 74% of the total growth containing 96% free cells. Cellular adherence to substrate particles was found to play an active role in the normal growth of the strain on -sitosterol. Unlike sodium acetate-grown cells, whose surface activity was negligible (60mNm^–1), the sterol-grown cells had strong surface activity (40mNm^–1). The high lipid content and long chain fatty acids in the cell-wall of -sitosterol-grown cells probably contribute to the high sterol adherence activity of the cells.     

Effect of temperature and additional carbon sources on phenol degradation by an indigenous soil <Emphasis Type="Italic">Pseudomonad</Emphasis>

A new indigenous soil bacterium Pseudomonas sp. growing on phenol and on a mixture of phenol, toluene, o-cresol, naphthalene and 1,2,3-trimethylbenzene (1,2,3-TMB) was isolated and characterized. Phylogenetic analysis suggested its classification to Pseudomonadaceae family and showed 99.8% DNA sequence identity to Pseudomonas pseudoalcaligenes species. The isolate was psychrotroph, with growth temperatures ranging from ca. 0 to 40 °C. The GC–MS structural analysis of metabolic products of phenol degradation by this microorganism indicated a possible ortho cleavage pathway for high concentrations (over 200 mg L^–1) of phenol. Biodegradation rates by this species were found to be three times more effective than those previously reported by other Pseudomonas strains. The effect of temperature on phenol degradation was studied in batch cultures at temperatures ranging from 10 to 40°C and different initial phenol concentrations (up to 500mgL^–1). Above 300mgL^–1 of initial phenol concentration no considerable depletion was recorded at both 10 and 40°C. Maximum degradation rates for phenol were recorded at 30°C. The biodegradation rate of phenol was studied also in the presence of additional carbon sources (o-cresol, toluene, naphthalene, 1,2,3-TMB) at the optimum growth temperature and was found significantly lower by a factor of eight in respect to the strong competitive inhibition between the substrates and the more available sources of carbon and energy. The Haldane equation =_m S/(K_S+S+S²/K_I) was found to best fit the experimental data at the optimum temperature of 30°C than the Monod equation with kinetic constants _m=0.27h^–1, K_S=56.70mgL^–1, K_I=249.08mgL^–1.     

Larvae of <Emphasis Type="Italic">Arnoglossus elongatus</Emphasis> (Pleuronectiformes: Bothidae) from northwestern Australia

Eleven postflexion larvae (9.1–23.9mm standard length: SL) of a bothid, Arnoglossus elongatus, from northwestern Australian waters were described. These specimens were characterized by vertebral numbers of 11–12+32–34=43–45, slender body, remarkably elongated second dorsal fin ray, and presence of melanophores on and slightly above midlateral line of body, plus on dorsal wall of abdominal cavity and air bladder (specimens >12.6mm SL), proximally on caudal fin rays (>16.5mm SL), and on pterygiophore zones of dorsal fin and anal fin (>23.8mm SL).     

Competition between <Emphasis Type="Italic">Eucalyptus victrix</Emphasis> seedlings and grass species

Competition in a natural system may be interspecific or intraspecific. In semiarid ecosystems, competition for resources between established neighboring grass species and newly recruited seedlings is very high. To examine the effects of grass species density, growing space and time of establishment on Eucalyptus victrix seedlings (interspecific competition), and the effect of density and growing space within E.victrix (intraspecific competition) we conducted an experiment under controlled conditions. We tested four hypotheses (i) E.victrix seedling growth is not affected by grass density; (ii) there is no difference in E.victrix survival and growth between early and later grass establishment; (iii) interspecific competition is not more intense than intraspecific competition in E.victrix; and (iv) growth of E.victrix seedlings is not dependent on available growing space. In a monoculture of E.victrix, seedling mortality was higher (10%) in large pots. In mixed culture pots, where E.victrix seedlings and grass seedlings were planted on the same day, E.victrix seedlings survived for up to 4weeks, but started to die after week five in the smallest pots. However, mortalities occurred in pots of all sizes when grass was established before E.victrix seedlings. Results also indicated that the resources necessary for the growth of individual E.victrix seedlings were more limiting under conditions of increased density of neighboring grass species rather than intraspecific competition. In particular, photosynthetic area of E.victrix seedlings was drastically reduced in mixed cultures. Although density, pot size and time of planting had impacts on E.victrix seedlings, the patterns of these impacts were variable.     

<Emphasis Type="Italic">Uncisudis posteropelvis</Emphasis>, a new species of barracudina (Aulopiformes: Paralepididae) from the western North Pacific Ocean

Six specimens (2 flexion larvae: 9.5–10.4mm in notochord length; 4 postflexion larvae: 12.3–18.2mm in standard length) collected from the western North Pacific are tentatively ascribed to the genus Uncisudis of the tribe Lestidiini of the subfamily Paralepidinae (Paralepididae) in sharing remarkably elongate and filamentous pelvic fin rays, their tips reaching the origin of the anal fin. They are described as Uncisudis posteropelvis sp. nov. in uniquely having the insertion of pelvic fins closer to the origin of anal fin than to the posterior end of dorsal fin base among lestidiine species. Addition to this character, the new species has remarkably elongate and filamentous dorsal fin rays, the short distance between anus and origin of anal fin (4.2–6.1% of standard length, SL), the posteriorly located pelvic fins (prepelvic length 69.4–71.5% SL), dorsal fin rays 10, anal fin rays 28–29, myomeres 41–42+38–40=80–81 (vertebrae 38+41=79), and peritoneal pigment spots 11–12. The occurrence of larvae differing in pigment pattern from the present new species suggests another undescribed species of Uncisudis in the western South Pacific.     

Consequences of harvesting for genetic diversity in American ginseng (<Emphasis Type="Italic">Panax quinquefolius</Emphasis> L.): a simulation study

American ginseng, Panax quinquefolius L., is one of the most heavily traded medicinal plants in North America. The effect of harvest on genetic diversity in ginseng was measured with a single generation culling simulation program. Culling scenarios included random harvest at varying levels, legal limit random harvest and legal limit mature plant harvest. The legal limit was determined by the proportion of legally harvestable plants per population (% mature plants per population). Random harvest at varying levels resulted in significant loss of genetic diversity, especially allelic richness. Relative to initial levels, average within-population genetic diversity (H _e) was significantly lower when plants were culled randomly at the legal limit (Mann–Whitney U=430, p<0.001) or when only mature plants were culled (Mann–Whitney U=394, p<0.01). Within-population genetic diversity was significantly higher with legal limit mature plant harvest (H _e=0.068) than when plants were culled randomly at the legal limit (H _e=0.064; U=202, p<0.01). Based on these simulations of harvest over one generation, we recommend that harvesting fewer than the proportion of mature plants could reduce the negative genetic effects of harvest on ginseng populations.     

Effects of tidewater on the feeding ecology of hooded crane (<Emphasis Type="Italic">Grus monacha</Emphasis>) and conservation of their wintering habitats at Chongming Dongtan,China

Dongtan (or East Tideland) on Chongming Island in China is an important wintering site of Grus monacha (hooded crane). Field observations were conducted in Dongtan in the wintering season of 2000–2001 to determine how tidal fluctuation affects the habitat use and behavior of G.monacha. Scirpus mariqueter (sea-bulrush) was the dominant species in the tidal vegetation; and its corms were the major food source for G.monacha. The corms in the outer zone (far from the dyke) were buried underground shallower than those in the inner zone (near the dyke) because of erosion by tidewater. For easy access to food, G.monacha tended to select the outer zone and the edge of tidal creeks as its foraging sites for the majority of time spent on the tideland. Regression analysis revealed that distance of the foraging sites to the dyke was correlated with tidal height. The cranes did not appear to show territorial behavior, and tended to form large-sized flocks, especially at high tide, because of the effect of the tidewater and the non-uniform distribution of food. Thus, the height of the tide is an important factor responsible for the habitat selection of G.monacha, which was also the major cause of the cranes selecting only the natural tideland at Dongtan on Chongming Island. Unfortunately, the habitats of G.monacha are limited, and even threatened, at Dongtan because the tideland is frequently reclaimed. Appropriate measures should be taken to prevent the tideland being further reclaimed, otherwise the natural wintering grounds of G.monacha will soon disappear.     

<Emphasis Type="Italic">Cocotropus keramaensis</Emphasis>, a new species of the family Aploactinidae (Teleostei) from the Kerama Islands,southern Japan

A new species of aploactinid, Cocotropus keramaensis, is described based on a single specimen collected off the Kerama Islands, southern Japan. This new species is separable from other known congeners in the following combination of characters: XII, 10 dorsal fin rays; II, 7 anal fin rays; 13 pectoral fin rays; 26 vertebrae; 4+8=12 gill rakers; five distinct preopercular spines; upper jaw longer than the lachrymal; single papilla on the posterior portion of the maxilla; outer edge of the lower jaw with four distinct papillae; first sensory pore of the lower jaw on both sides fused; anterior tip of the isthmus reaching to the fifth sensory pore of the lower jaw; and anterior four dorsal spines anterior to the third neural spine.     

Carbon dynamics and budget in a <Emphasis Type="Italic">Miscanthus sinensis</Emphasis> grassland in Japan

We investigated the carbon dynamics and budget in a grassland of Miscanthus sinensis, which is widely distributed in Japan, over a 2-year period (2000–2001). Plant biomass began to increase from May and peaked in September, then decreased towards the end of the growing season (October). Soil respiration rates also exhibited seasonal fluctuations that reflected seasonal changes in soil temperature and root respiration. The contribution of root respiration to total soil respiration was 22–41% in spring and summer, but increased to 52–53% in September. To determine the net ecosystem production (carbon budget), we estimated annual net primary production, soil respiration, and root respiration. Net primary production was 1207 and 1140gCm^–2 in 2000 and 2001, respectively. Annual soil respiration was 1387gCm^–2 in 2000 and 1408gCm^–2 in 2001; root respiration was 649 and 695gCm^–2 in 2000 and 2001, respectively. Moreover, some of the carbon fixed as net production (457–459gCm^–2) is removed by mowing in autumn in this grassland. Therefore, the annual carbon budget was estimated to be –56gCm^–2 in 2000 and – 100gCm^–2 in 2001. These results suggest that the Miscanthus sinensis grassland in Japan can act as a source of CO₂.     

Development of high frequency multiple shoot formation in Persian clover (<Emphasis Type="Italic">Trifolium resupinatum</Emphasis> L.)

An efficient and reliable micropropagation system for Persian clover (Trifolium resupinatum L.) was developed using different explants and media. Node, hypocotyl and cotyledonary node explants were cultured on Murashige and Skoog (MS) medium supplemented with combinations of either 6-benzyladenine (BA) and indole-3-butyric acid (IBA) or BA, Kinetin (KIN) and IBA. Direct multiple shoots developed within 6weeks in all explants in most media tested. The best shoot multiplication capacity was obtained from cotyledonary node explants on MS medium containing 7.1M BA and 1M IBA or 14.1M BA and 1M IBA. Elongated shoots were rooted on either MS medium alone or combination with different concentrations of indole-3-butyric acid (IBA), indole-3-acetic acid (IAA) and -naphthaleneacetic acid (NAA). High rooting was achieved in half strength MS medium containing 8M IBA.     

Carbon dioxide and water vapor exchange over a <Emphasis Type="Italic">Miscanthus</Emphasis>-type grassland: Effects of development of the canopy

The eddy correlation technique was employed to measure net ecosystem carbon dioxide (CO₂) (NEE) and water vapor exchange (LE) over a C3/C4 co-occurring wet temperate Miscanthus-type grassland in the Kanto plain of Japan in the 1999 growing season. The maximal mean canopy height and maximal leaf area index were 1.0m and 5.5, respectively. The daily maximal LE was approximately 540Wm^–2. The maximum value of daily accumulative LE was 16.3MJday^–1. Daily variation of the decoupling factor () suggests that in the morning LE decoupled with the atmosphere, and the available energy was the major driving force for LE, whereas in the afternoon LE coupled strongly with the atmosphere, and the atmospheric evaporative demand played a critical role in LE. The decline in (from 0.8 to 0.5) with the growing season demonstrates that LE decoupled from the atmosphere in the later growth season. The peak NEE value was 57.4µmolCO₂m^–2s^–1 (the positive value signifies the canopy carbon gain was from the air). The maximal daily integrated NEE was 1.06molCO₂m^–2day^–1 observed during the peak growth stage. A rectangular hyperbolic model was used to describe the relation between daytime NEE and incident photosynthetic photon flux density (PPFD). The net ecosystem CO₂ was not light-saturated up to a PPFD level of 2000µmol m^–2s^–1. The initial slope estimated with the NEE–PPFD response model was approximately 0.042molCO₂mol^–1photon on average. The canopy light compensation point ranged from 210 to 430µmolm^–2s^–1 with an average of approximately 310µmolm^–2s^–1. Both the initial slope and the canopy light compensation point decreased as the canopy senesced. The switch in dominance from C3 to C4 plants played an important role in the canopy fluxes.     

Cold-hardiness of Dermacentor marginatus (Acari: Ixodidae)

The cold-hardiness of Dermacentor marginatus using laboratory-reared offspring of ticks collected in Germany was characterized. Investigations of unfed stages revealed that adult ticks suffered 50% mortality at –10°C after 4–5 months, but larvae and nymphs suffered mortality within few days, whereas –15°C was lethal for all stages within a very short period. Larval hatch and moulting of engorged larvae and nymphs did not occur at 10°C. Embryonic development of eggs with larval hatch was considerably reduced by exposure of eggs to 10°C. Engorged females did not lay eggs at 10°C, the oviposition capability, however, persisted over 6 months at 10°C, 5 months at 5°C, 3 months at 0°C and 2 months at –10°C without substantial decrease of the oviposition capacity or reduction of viable eggs. These results present evidence that unfed adult ticks are the ecoepidemiologically most effective stages, which are capable to tolerate long and extremely cold winters without substantial impairment of the population density. It is also considered that engorged females interrupt their oviposition at low and subzero temperatures delaying it for months and so contribute in bypassing winter conditions. None of the stages survived supercooling indicating that D. marginatus is freeze intolerant. Mean supercooling point (SCP) ranged between –26°C in eggs and –12, 6°C in engorged females. Compared with eggs, the SCP of the other stages was significantly higher. In conclusion, the SCP is considered to have no predictive value in the context with cold-hardiness.     

Ontogeny of the mandarinfish <Emphasis Type="Italic">Siniperca chuatsi</Emphasis> (Perciformes: Sinipercidae) reared in aquarium

Early-stage morphologies of the mandarinfish Siniperca chuatsi are described on the basis of an ontogenetic series of reared specimens in an aquarium. Spherical eggs (diameter 1.70–1.82mm) with a single oil globule (0.40–0.48mm) were free-demersal and easily floated when agitated. Hatching occurred about 3 days after spawning at about 24°C. Newly hatched larvae (3.8–4.2mm in notochord length: NL) had many melanophores on the yolk sac. After reaching ca. 5.5mm NL (8–9+19–20=27–28 myomeres), larvae had almost completely absorbed the yolk, possessed a large mouth and sharp teeth, and were starting to prey on other fish larvae. Three large preopercle spines appeared at ca. 5.5mm NL, five spines by ca. 8.5mm NL, and eight by ca. 21mm in standard length (SL). The interopercle bore a single spine at ca. 8.5mm NL and two spines at ca. 13.5mm SL. A single spine appeared at the supracleithrum and another at the opercle at ca. 10mm SL. Dorsal fin spines and pelvic, anal, and caudal fins were completed at ca. 10mm SL. Dorsal fin rays and pectoral fins were completed at ca. 13.5mm SL. Four ontogenetic characters (free-demersal eggs, large jaws with large teeth, conspicuous head spination, and precocious completion of dorsal fin spines) are rare among freshwater percoids.     

Assessment of within-population genetic structure in <Emphasis Type="Italic">Quercus crispula</Emphasis> and <Emphasis Type="Italic">Q. dentata</Emphasis> by amplified fragment length polymorphism analysis

The spatial genetic structure was assessed by amplified fragment length polymorphism (AFLP) technique for Quercus crispula Blume (37 individuals) and Q.dentata Thunberg (54 individuals) growing along a 550-m transect in Ishikari, Hokkaido, northern Japan. The simple Mantel test revealed significant negative correlation between genetic similarity and geographic distance in Q.dentata and negative but insignificant correlation in Q.crispula. Spatial autocorrelation analysis revealed that Mantels r generally decreased from positive to negative values with the increase of spatial distance in both oak species with significant deviation from zero for the 50–100-m (positive) and 250–300-m classes (negative) in Q.dentata. Thus, significant spatial genetic structure was revealed at least in Q.dentata     

Effects of domestication and agronomic selection on phytoalexin antifungal defense in <Emphasis Type="Italic">Phaseolus</Emphasis> beans

Systems of wild and cultivated relatives are good experimental systems to test chemical defense theory because they provide closely related varieties that differ in discrete traits. To determine the relationship between resistance and chemical defense diversity among wild, landrace and cultivar accessions of Phaseolus vulgaris, we measured resistance to fungal infection in laboratory and field experiments, quantified phytoalexin diversity, and assessed the effectiveness of phytoalexin mixtures extracted from live tissue. Results show a gradient of resistance to fungal infections between wild, landrace and cultivar varieties. In the laboratory, wild seedlings were more resistant (93% non-infected) than landrace seedlings (80% non-infected) and modern cultivar seedlings (68% non-infected). Under field conditions wild seedlings were more resistant (97% non-infected) than cultivar seedlings (71% non-infected). Wild seedlings presented the highest phytoalexin diversity (H=1.11), while those of the landrace presented an intermediate level (H=0.97) and cultivar seedlings presented the lowest diversity (H=0.93). No differences were found in total concentrations. The in vitro inhibitory properties on hyphal growth of the isoflavonoid mixtures produced by individual seedlings showed a similar trend. Our results are consistent with similar gradients in other species of Phaseolus beans and resistance to Colletotrichum sublineolum in sorghum.