Colletotrichum destructivum was isolated from infected seeds and pods of cowpea (Var. IAR-48) with typical symptoms of anthracnose disease. The fungus during the pathogenesis, reduced the protein, fat, ash, crude fibre, carbohydrate, calcium and phosphorus, and increased the amount of iron, sodium, zinc, magnesium and potassium in the infected seed and husk. The carbohydrate, protein and phosphorus contents in the healthy husk reduced from 55.05%, 11.21% and 171.85 mg to 39.94%, 8.92% and 42.92 respectively in the infected sample whereas potassium and sodium contents in the healthy pod increased from 1.03 mg and 78.29 to 2.90 mg and 100.65 mg respectively in the infected husk. The potassium, sodium, magnesium and iron increased from 1292.25 mg, 0.19 mg, 0.09 mg and 11.00 mg in the healthy seeds to 1536.03 mg, 0.28 mg, 0.21 mg and 13.19 mg respectively in the infected seeds. The fungus caused the depletion of phosphorus from 498. 06 mg in the healthy to 430.17 mg in the infected seed, protein from 24.09% to 17.86%, carbohydrate from 57.02% to 34.35%, fat from 1.70% to 1.33% and crude fibre from 3.94% to 2.61%. The average loss of the major nutrient values; protein, carbohydrate and fat were 28.95%  and 22.55% for seed and husk respectively after 8 weeks of planting.

Colletotrichum destructivum during pathogenesis reduced the nutrient values of cowpea leaf and stem. The protein, fat, carbohydrate, fibre contents of the leaf decreased from 34.91%, 5.42%, 43.61% and 19.46% in the uninfected leaf samples to 20.40%, 2.15%, 37.03% and 15.53% in the infected leaf respectively whereas the moisture and ash contents increased by 10.88% and 11.15% in the uninfected leaf sample to 12.51% and 11.24% respectively in the infected leaf samples. The composition of zinc, sodium, magnesium, iron, and potassium in the leaf increased whereas calcium and phosphorous decreased after inoculation with the test fungus. It reduced the protein content from 15.64% in the healthy stem tissue to 12.69% in the infected one, fat from 1.29% to 0.78%, crude fibre from 16.87% to14.62%, and carbohydrate from 31.11% to 25.39%. Also, the fungus caused a reduction of the calcium and phosphorus contents of the healthy stem tissue from 2.09 mg and 326.50 mg to 1.19 mg and 299.10 mg respectively. Infection of the stem with the pathogen led to increasing moisture, potassium, sodium, zinc, iron, and magnesium contents from 11.80%, 230.12 mg, 111. 28 mg, 1.66 mg, 0.89 mg and 0.95 mg to 12.65% , 364.21 mg, 203.64 mg, 3.02, 1.52 mg, and 2.18 mg respectively. The average loss of the major nutrients; protein, fat, and carbohydrate was more in the leaf than stem, 34.29% and 18.14%  respectively 8 weeks after planting (WAP).