agronomy test 1

1. Hardy plants growing in hot climate and arid regions all year round

2.Cultivated in most soil types EXCEPT clay

3.Low tolerance for moist and saline soil conditions

3. Develop yellow leaves  due to poor soil adration and N deficiency on compacted soils---> drain poorly

4.Do best on loamy soils--------> rich in O.C (> 2%)

1. Soil should have CEC > 80 mmol/kg

2. grow best on slightly acidic to mildly alkaline soils of pH 6.1 - 7.8

3. High yields correlated with : 

   -high pH 

   -high levels of exchangeable bases

   -base saturation in topsoil and subsoil

Plant nutrition

1. decline of sisal yields ----> depletion of plant nutrition & lack of manuring and fertiliser

2. husbandry------> it is resilient to disease & input requirement is low

3. 30 - 50 kg N/year

4. P requirement of  10 mg P/kg

5. removes significant amounts of : 

    Ca 50 mmol Ca/kg

    Mg 17 mmol Mg/kg

    K 2.5 mmol K/kg

1.Sisal weevil only natural enemy----> reach pest proportions

2. Adults bore into leaves of young plants & if perforated ------> sisal hearts are infected with fungi

3. Central shoot become red and soft ----->producing conditions suitable for development of larvae-----> die quickly in absence of moisture

Scyphophorus acupunctatus

1. Fibers lying longitudinally in leaves------> removed from leaves as soon as they are cut

2. To avoil damage during cleaning

3. Fiber removed by scraping away pulpy material by mechanical decortication process ans hand *********

1.unsuitable--->Heavy clays and soils of gravelly or dry sandy nature

2.does best on well-drained soils with good waterholding capacity

3.Loamy soil with high organic material contents and a pH 6.0-7.0----> for production

4. compacted layers in the soil must be removed before planting due to tap root system