Cover crops (also written in a single word, i.e., covercrops) are plants grown primarily to prevent the soil from being eroded by wind and water.
In addition, they help regulate soil temperature, suppress weed growth, reduce pests and diseases, minimize loss of water from the ground through evaporation, enhance soil fertility, add organic matter to the soil, improve soil aeration, and promote high water infiltration.
Marcotting or air layering, an asexual or vegetative method of plant propagation, can be easily performed with less skill.
Air layering is just slightly different from other methods of layering such as tip layering, simple layering, compound or serpentine layering, etc.
In all these methods, the induction of root development is usually done by wounding the part of the plant to be rooted.
In this layering method, roots are induced to form on the part of the plant while it remains aerial (aboveground), hence the term air layering.
But in other layering methods, the same plant part is rooted on the ground usually by bending it downward.
Intercropping and crop rotation are alternative strategies applied in multiple cropping, the growing of two or more crops in the same piece of land.
Both cropping systems have resulted in increased farm production and profitability per unit of land area in selected crops.
Intercropping is the growing of two or more crops together in proximity on the same land. As a result, two or more crops are managed at the same time.
It differs from crop rotation in which two or more crops are grown one after the other.
There are at least four types of intercropping according to the spatial arrangement (Sullivan, 2003).
Kaong or sweet palm is a promising cash crop with potential for the establishment of plantations or, at the least, for deliberate growing to supplement the natural stands.
It has been noted that the worldwide demand for the processed products of this palm continues to grow, but the supply of raw materials is limited by the number and accessibility of natural stands.
These natural sources are dispersed.
The fibrous root system is one of two main types of roots according to the origin of development and branching pattern in the angiosperms.
The other is the taproot system.
Generally, plants with a taproot system are deep-rooted in comparison with those having fibrous types.
The taproot system enables the plant to anchor better to the soil and obtain water from deeper sources.
In contrast, shallow-rooted plants are more susceptible to drought but they are quick to absorb surface and irrigation water and thus have the ability to respond quickly to fertilizer application.
In order to enhance the development of more lateral roots in tap-rooted plants, pruning of the taproot is practiced, as in plant nurseries.
The practice is also a standard procedure with bonsai trees.
The essential elements (or essential nutrients) are chemical elements that are absolutely needed by plants for their growth and development.
Their essentiality has been established based on the following criteria formulated by D. I. Arnon and P.R. Stout (1939):
1. An element is essential if, being deficient, the plant is unable to complete the vegetative or reproductive stage of its life cycle;
2. The deficiency can be prevented or corrected only by supplying the specific element causing the deficiency; and
3. That element is directly involved in the nutrition of the plant.
With time, it has become apparent also that there is an additional fourth criterion: that the essentiality of any element is proved in all plants tested.
There are four climate types in the Philippines according to the Modified Corona’s Classification of Climate.
These are the Types I, II, III, and IV.
This system of climate classification was devised by Fr. J. Corona in 1920 (Lantican 2001) and is based on average monthly rainfall.
Accordingly, a dry month is one with less than 50 mm of rainfall but also considers dry a month having more than 100 mm of rainfall that comes after three or more very dry months.
Country-wide, the Philippines has a tropical climate with a relatively high temperature and humidity having abundant rainfall.
This climate is largely similar to those of countries in Central America (kidlat.pagasa.dost.gov.ph, accessed January 28, 2011).
The urea fertilizer, also popularly called forty six zero zero (46-0-0), is a simple or straight (single-element) fertilizer that supplies the major essential element nitrogen in ammonic form (NH4+).
The positively charged ammonium ion (NH4+) is nonvolatile and is one of the two forms of nitrogen that can be absorbed by plants, the other being nitrate (NO3–).
The plant leaves are the lateral outgrowth of the stem which develops from the meristematic tissues of buds.
They are the part of the plant shoot which serves as the chief food-producing organ in most vascular plants.
To perform this function more efficiently, they are arranged on the stem and oriented to allow maximum absorption of sunlight.
It is also via leaves that loss of water from the plant body primarily occurs through the process of stomatal transpiration and guttation.
C4 plants are those which photosynthesize following the mechanism called C4 Photosynthesis.
They are found only in the angiosperms with about 8,000 members in 17 families (see list below), equivalent to about 3% of all land plants.
Combined, the grasses (family Poaceae or Gramineae) and sedges (family Cyperaceae) comprise roughly 79% of the total number of C4 species (Simpson 2010).
