rosy apple aphid, dysaphis plantaginea (passerini), with worldwide distribution is an important pest of apple orchards. host plant resistance is an essential component of integrated management of this insect pest. we investigated the resistance of seven apple cultivars, malus domestica (borkhausen), namely granny smith, starkrimson, golden smoothee, red delicious, golden delicious, boshghabi, a...

Although flowering in mature fruit trees is recurrent, floral induction can be strongly inhibited by concurrent fruiting, leading to a pattern of irregular fruiting across consecutive years referred to as biennial bearing. The genetic determinants of biennial bearing in apple were investigated using the 114 flowering individuals from an F(1) population of 122 genotypes, from a 'Starkrimson' (st...

Sorbitol dehydrogenase (l-iditol:NAD(+) oxidoreductase, EC 1.1.1.14) has been detected and characterized from apple (Malus domestica cv. Granny Smith) mesocarp tissue cultures. The enzyme oxidized sorbitol, xylitol, l-arabitol, ribitol, and l-threitol in the presence of NAD. NADP could not replace NAD. Mannitol was slightly oxidized (8% of sorbitol). Other polyols that did not serve as substrat...

Oxygen fugacity has been calculated for rutile–ilmenite assemblages from the reaction 2Fe2O3 (in ilmenite) C 4TiO2 (rutile) D 4FeTiO3 (in ilmenite) C O2. The equation log f O2 D 22:59 25925=T 3:09 log T C 0:0016535P C 48:836P=T 4 log a FeTiO3 C 2 log a Fe2O3 C 4 log a TiO2 , where T is in kelvin and P is in kbar, was derived from available thermodynamic data. The hypothetical end-member rutile–...

The effectiveness of initial low oxygen stress (ILOS) to control apple scald without postharvest application of scald inhibitors and fungicides was investigated. Scald susceptible (‘Granny Smith’, ‘Law Rome’, ‘Red Delicious’) and not susceptible (‘Idared’) fruits were harvested preclimacterically and treated at 1°C with (1) ILOS pretreatment or (2) no pretreatment as control. Fruit were then st...