Anthracnose (fungus – Glomerella cingulata): The fungus which causes anthracnose attacks both the fruit and the foliage. Infected fruit are characterized by a soft rot and premature dropping of the fruit. Immature fruit are dried up and may remain on the tree. Infection results in a small, sunken, discolored area. The areas enlarge with age and become covered with a pink mass of spores. Affected leaves will have a dark brown margin. Defoliation occurs with increased infection. Sanitation is extremely important in the fig planting. Diseased fruit as well as infected leaves should be removed.
Cotton Root Rot: (See Section on Cotton Root Rot)
Crown Gall: (See Section on Crown Gall)
Dieback (physiological – cold injury): Fig trees are often injured by early or late frosts that kill younger twigs. Although their death is not related directly to loss in production, they may serve as a site for secondary fungi to get started. All dead twigs and limbs should be pruned from the trees.
Fig Mosaic (virus): Affected figs show large yellow areas in the leaves, oak leaf pattern, ring spot area, or a mild mottled pattern. Leaves may be smaller than normal and deformed. Premature defoliation and fruit drop often occur. The virus is spread by vegetative cuttings and Aceria ficus (eriophyid mite). Control is by selection of clean propagating stock and insect control.
Fig Rust (fungus – Physopella fici): The disease is first evident as small, angular, yellow-green flecks on the leaf. The spots do not become extremely large but do become more yellow and finally a yellowish-brown. The margin of the spot is reddish in color. On the upper surface the spots are smooth, while on the lower surface the spots appear as small blisters. Brown spores are released from the blisters at maturity. As infection continues, the leaves become more yellow, and finally they begin to die around the leaf margins. Eventually death and defoliation occur. Complete defoliation can occur in two or three weeks. Fig rust generally becomes a problem as the fruit reaches maturity. Therefore, fungicide applications should be started in the early spring when the first leaves are completely grown. Make additional applications as new growth is formed. Do not spray when the fruit is one-fourth inch in diameter as the spray residue will make the fruit unattractive. Resume spraying after the fruit has been harvested.
Fruit Drop (physiological – flower development): The fig produces four types of flowers (male, female, Gall, and Mule): The male and female flowers are most often associated with the Capri type fig. This fig requires a wasp for pollination. The wasp does not occur in this part of the United States, thus it is impossible to grow Capri figs in Texas. Gall flowers are imperfect female flowers. They are found only on Capri and Cordelia figs. Mule flowers need no pollination and produce no seeds. The common fig grown in Texas produces primarily mule flowers. Since no seed are formed, the mule flowers are more subject to dropping than than those flowers which require pollination. The presence of the seed and the growth hormones produced by the seed help prevent fruit drop. The figs grown in Texas due to absence of seed are more subject to premature fruit drop as a result of adverse growing conditions.
Leaf Blight (fungus – Pellicularia kolerga): In early stages of infection, small areas in the leaves become yellow and appear watersoaked. With continual development, the upper surface becomes silvery white, and the lower surface becomes light brown and covered with a thin fungal web. In most cases, the leaves will turn brown and shrivel. It affects primarily the leaves but may develop on some fruit if it is new and a severely affected leaf or stem tip. Sanitation is the only recommendation to reduce losses from this disease.
Limb Blight (fungus – Corticum salmonicolor): Affected limbs wilt rapidly. The fungus enters at a spot along the main or secondary limbs, and all leaves die beyond that point. The fungus enters at a dead fruiting spore or at some other injured spot. All dead twigs and limbs should be removed by pruning so that they will not serve as infection sites.
Mushroom Root Rot: (See Section on Mushroom Root Rot)
Root Knot Nematodes (nematode – Meloidogyne spp.): Root knot is one of the most common disease problems occurring on figs. Infected roots are characterized by small galls or swellings on the roots. The presence of the galls on the roots interferes with the normal uptake of nutrients by the roots. Plants infested with root knot are stunted and have a general unhealthy appearance. Infested planting sites should be treated with Vapam prior to planting. This will reduce the nematodes in the soil to a low level. Do not use around living plants as it will result in severe root pruning, and in many cases death will occur. Make sure the fig plant is free of root knot. Once planted, the only practice left is to keep the plant in good health with regular fertilizer applications and maintain adequate moisture around the plant. If nematodes were initially present, the fig will eventually become infested, but the root system should be well established by then. (See Section on Root Knot Nematodes)
Sclerotium Blight (fungus – Sclerotium rolfsii): A yellowish-white mat of fungal growth is formed at the base of the plant. Round, hard, yellowish to brown bodies (sclerotia) are found scattered in the fungal growth. To prevent the occurrence of this disease, it is important to carry out a thorough sanitation program. Old leaves or grass around the base of tree will encourage fungal development.
Souring (several fungi and bacteria): Organisms are carried into the fruit by the dried fruit beetle. Figs which have open “eyes” or ostioles should not be planted. Only those with closed “eyes” should be planted. Some examples of closed eye figs are Celest, Texas Everbearing, and Alma. No chemical control has been found to be totally effective. Maneb fungicide will help to some extent. Insects should be controlled to eliminate them as carriers for the disease causing organisms.
Table 1: Fig Varieties and Their Reaction to Souring