الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 261 |  |  |
| | | from | 261 | | |
Abstract
This work was aimed to:
1. Examine the growth of guava seedlings to select the species of AMF that can
help to improve the growth of guava seedlings, soil microbial activity, and
uptake nutrients.
2. Examine the growth of guava seedlings to select the rate of biochar was
effective on plant growth and N, P, and K uptake in guava (Psidium guajava L.)
seedlings and improved microbial activity in the soil.
3. Examine the growth of guava seedlings to select the rate of vermicompost was
effective on plant growth and N, P, and K uptake in guava (Psidium guajava L.)
seedlings and improved microbial activity in the soil.
4. Evaluation of the effect of treatment with mycorrhizal fungi, biochar,
vermicompost, and the mixture between them on guava seedlings.
Four experiments were conducted on pots in one of the guava nurseries at Rosetta
City, Bahria, Egypt, to studies:
A. Effectiveness of three arbuscular mycorrhizal species on the growth of
guava seedlings.
Plastic pots (20 cm in diameter and 18 cm depth) were washed, labeled, and a filter
paper was placed on the bottom of all pots to prevent soil seep, then a weight of 3 kg
soil was placed for each pot with leaving 5 cm upper without soil and compacted to
bulk density of about 1.42 g cm-3. One week before planting, all pots were watered to
the volumetric moisture content 0.25 cm3cm-3, which corresponds to 70% of soil field
capacity. Then seedlings of Guava (Psidium guajava L.) were put in pots on March 6,
2020. Basal applications of N and K fertilizers were added to each seedling at a rate of
30 g NH4NO3 and 20 g K2SO4 per seedlings. The N fertilizer was applied at four equal
doses at the rate of 7.5 g/60 ml water for each pot. The K fertilizer was applied before
putting the soil in the pots. Three levels of phosphorus fertilizer (calcium
superphosphate (15.5 % P2O5)) were applied before filling the pots to obtain P0
(without P fertilizer); P1 (50% of recommended P fertilizer (15 g / seedling) and P2
(100% of recommended P fertilizer (30 g / seedling) (Hernandes et al., 2012). In AMF
pots, the soil was mixed with 30 ml of AMF inoculums one week before planting
(Malibari et al., 1990). Also, 20 ml of AMF inoculums were added with the seedlings
of Guava, (in total, the rate of 500 A-mycorrhizal spores per pot). All pots were irrigated
with tap water every day to keep the soil at 70% of its field capacity by the usual
weighting of pots. The guava seedlings were harvested 120 days after planting (the
harvest date July 7, 2020). At the harvest time, shoots of all guava seedlings were
separated from roots. The shoots and half of the roots (by weight) were washed with
tap water, distilled water, air dried, and over- dried at 70°C for 48 hours (Steyn, 1959)
to constant weight, and the guava shoots and half roots dry weight were recorded, then
grounded in a mill and stored in paper package for chemical analysis.