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Sodium alginate was used to prepare pelletized formulations for each of five fungi. Aqueous mixtures of 1.0% (w/v) sodium alginate and homogenized mycelia ofAlternaria cassiaeJurair & Khan,Alternaria macrosporaZimm.,Fusarium lateritiumNees ex Fr.,Colletotrichum malvarum(A. Braun & Casp.) Southworth, or aPhyllostictasp. were pelletized by dropwise additions of each mycelial-alginate mixture into 0.25 M CaCl2. Abundant conidia were produced on the pellets 24 to 48 h after the pellets were spread into trays and exposed 10 min/12 h to 275-W sunlamps. These conidia germinated readily (90 to 100%) and readily infected the respective host plants. Each liter of mycelium plus growth medium from submerged liquid cultures produced 4 L of the mycelial-alginate mixture. Each liter of the mycelial-alginate mixture produced approximately 18 g of air-dried formulation. When 10% (w/v) clay was incorporated into the pellets, each liter of the mycelial-alginate mixture produced approximately 118 g of air-dried formulation. The pelletized fungi sporulated readily following storage at 4 or 25 C for 6 to 8 months. This method of pelletization is potentially useful for the formulation of inoculum of fungi used as mycoherbicides, for the mass production of pycnidium-forming fungi, and for the production of inoculum for host-plant resistance studies.

Volatile emissions from residues of the winter cover legumes, Berseem clover (Trifolium alexandrinum L.), hairy vetch [Vicia hirsuta (L.) S.F. Gray], and crimson clover (Trifolium incarnatum L.), inhibited germination and seedling development of onion, carrot, and tomato. Using GC-MS, 31 C2-C10 hydrocarbons, alcohols, aldehydes, ketones, esters, furans, and monoterpenes were identified in these residue emission mixtures. Mixtures of similar compounds were found in the volatiles released by herbicide-treated aerial and root residues of purple nutsedge (Cyperus rotundus L.) and the late-season woody stems and roots of cotton (Gossypium hirsutum L.). Vapor-phase onion, carrot, and tomato seed germination bioassays were used to determine the time- and concentration-dependent inhibition potential of 33 compounds that were either identified in the plant residue emissions or were structurally similar to identified compounds. Cumulative results of the bioassays showed that (E)-2-hexenal was the most inhibitory volatile tested, followed by nonanal, 3-methylbutanal, and ethyl 2-methylbutyrate. All the volatile mixtures examined contained at least one compound that greatly inhibited seed germination.