3.2. Yield and yield components
In mycorrhizal (+AM) and nonmycorrhizal (−AM) plants, total and marketable yields decreased sharply in response to pH 3.5 + Al. The lowest marketable production observed on plants treated with
aluminium in comparison to low pH and control (pH 6.0) treat- ments was mainly attributed to a reduction in both the number of zucchini fruits per plant and the mean weight (Table 1). Moreover, with pH 3.5 and pH 3.5 + Al, the percentage of yield reduction in
comparison to control was significantly lower in +AM than −AM
plants, with the highest yield reduction recorded with pH 3.5 + Al
in comparison to those recorded with pH 3.5 treatment (Table 1). Irrespective of nutrient solution pH level and aluminium concen- tration, the marketable yield was significantly higher by 14.7% in
zucchini plants supplied with AM inoculum (avg. 3.9 kg plant−1 ) in
comparison to the noninoculated plants (avg. 3.4 kg plant−1 ).