CROP SCIENCE 1
2nd Written Examinations
2nd Semester 2000-01
14 March 2001
I. Identification (2 points each)
- Any living organism that contributes to losses in crop production.
- Art and science of improving the genetic make-up of plants with the
purpose of getting desirable recombinants that would suit the environment to
which they will be grown for efficient productivity.
- Living organism which posses 6 legs, one or two pairs or wings, and one
pair of antennae.
- Pollen dehisced before stigma becomes receptive.
- Male and female flowers seperated but borne on the same plant; self
pollination and cross-pollination are possible.
- Pierces the plant tissue and feed on the plant sap.
- Refers to the development stage of the crop when it has developed the
ability to ripen normally after harvest.
- An insect that inflicts direct damage on the crop plants.
- Literally, a pert that has a backbone. This term is generally applied on
rodents, birds, monkeys, bats, etc.
- (syn. Carrier), primarily used to describe the participation of insects in
the spread of pathogens.
- Any undesirable plant growing in agricultural field.
- Refers to the stage of development of the plant parts preferred by the
consumer. It is the basis for deciding when to harvest for an intended use.
- Plants with long narrow leaves and parallel veins arranged in two rows
along the stem and round, hollow stems.
- Sedges are similar to grasses but the leaves are aligned up and down the
stem in 3 rows and the stems are solid and triangular.
- Is a physical or physiological condition of a viable seed that prevents
germination even in the presence of otherwise favorable germination
condition.
- A collection of all the available seeds of a given crop species of both
locl and foreign sources.
- The external manifestation of a disease.
- Is a mature fertilized ovule that possesses an embryonic plant, stored
food material and protective coat.
- Evidence of the presence of pathogens.
- Serious outbreak of a disease.
- Transfer of a pollen from an anther to the stigma.
- Unicellular plant that are also parasitic on crop plants.
- Is the first operation in the postharvest life of a crop.
- Organisms that consist of a DNA strand inside a protein coat. Many are
transmitted (vectored) by insects.
- Male and female flowers seperated but borne on the same plant; self and
cross-pollination are possible.
II. True or False (2 points each)
- Chewing insects are insects that feed on the plant by removing pieces of
plant tissues.
- Emasculation is the killing or removal of the male part of stamens of the
flower to prevent self pollination; to develop female parent.
- Chasmogamous means pollination occurs after flower opening, cross
pollination possible.
- Dichogamous means male and female parts differ in maturity, more of cross
pollination.
- Nematodes are tiny (microscopic) worms that feed on plant roots.
- Protogyny means stigma receptive before pollen is dehisced; female flowers
mature earlier than males.
- Fungi are tiny multicellular plants that parasitize crop plants.
- Dioecious means male and female flowers borne on seperate plants, only
cross-pollination is possible.
- Self-incompatibility means that male and female flowers are present but
cannot pollinate each other.
- The leaves of broadleaf weeds are usually wider that those grasses and
sedges. Secondary vein network emerge from the primary vein in the leaf.
III. Enumeration (2 points each)
- The three emasculation techniques.
- The four basis for conducting plant breeding trials.
- The three criteria of essentiality of an element (fertilizer).
- Five methods of fertilizer application when there is already a standing
crop.
BONUS: (10 points)
Enumerate the four requirements in order to produce
quality compost.