Chaparral dodder is in the morning glory plant family. Dodder resembles a pile of yellow or orange straw wrapped lightly around its host plant. It is mostly stem; the leaves are really small on the stem’s surface, since they aren’t needed for photosynthesis while the dodder is obtaining nutrients from its host. It has tiny, white flowers that are 3mm wide, and fruits that are even smaller. Dodder’s conservation status is nationally secure, which means that there is plenty of it, and it is not rare. Native Americans used dodder for black widow spider bites. It was snuffed up the nose for nose bleeds, and they used it as scouring pads for cleaning. Some other names dodder has are love vine, strangleweed, devil’s hair, witch hair, and golden thread.
The Kumeyaay used to tell their children a story about the dodder plant. It was told that there were two villages, village one and village two, and they were enemies. One day, village one went to attack village two, but village one had to make sure that village two wasn’t going to come around and attack them first. So village one sent a young woman named Kwi-Kwi to go to the top of the hill and keep watch of village two, and if they were going to come around and attack her village, she would have to signal them. Kwi-Kwi became very hot and hungry, so she took a nap. While she was asleep, village two came around the hill and attacked village one first. When the warriors from village one came back to their village, they saw what had happened, so they marched to the top of the hill where Kwi-Kwi was and put a curse on her. Her hair turned long and orange. She ran away, and some of her hair ripped off. So, if you see dodder somewhere, that is where Kwi-Kwi has been.
The taxonomy of chaparral dodder is as follows:
- Kingdom - Plantae
- Division - Magnoliophyta
- Class - Magnoliopsida
- Order - Solanales
- Family - Convolvulaceae
- Genus - Cuscuta
- Species - C. Californica
Chaparral dodder is found in northern Baja California, north through California, Nevada, Arizona, Utah, Oregon, Washington, Idaho, Wyoming, and Colorado. The elevation where dodder can be found is between 0m to 2,780m. Chaparral dodder can be found in coastal, inland, mountain, desert and urban environments. Chaparral dodder lives in variety of plant communities within coastal, inland, mountain, desert, and urban environments.
C. californica is made up of eukaryotic cells. The nucleus in the eukaryotic cells is used to hold the DNA. The DNA is the genetic material. It tells the cell what to do. The DNA also makes partial copies of itself called RNA, and the RNA is used to arrange amino acids, which make up proteins. There are four different types of RNA: messenger RNA, which copies the genetic codes from the DNA and takes them to the cytoplasm; ribosomal RNA helps the ribosomes where proteins are assembled; and transfer RNA, which brings amino acids to the ribosomes, where they are joined together to form proteins.
The cell wall protects the cell and makes the plant rigid. Chloroplasts conduct photosynthesis, which means they make food using light energy. Dodder gets most of its energy from the host plant though. The vacuoles store water and nutrients. The vacuoles are bigger in plant cells than they are animal cells.
C. californica cells divide through mitosis, where the nucleus divides and the new cells have the same amount of chromosomes as the parent cell. The cell divides through mitosis for growth or when it needs to repair tissue. One other way that the cells divide is through meiosis. Meiosis is where the cell divides two times instead of one, and the new germ cells have only half the amount of chromosomes, so they can be used for sexual reproduction. Chaparral dodder produces pollen and ovules through meiosis.
Recent research has found that dodder takes out messenger RNA molecules from its host. The plants exchange messenger RNA, and then it seems dodder starts to control the host, though details are still unknown.
An aquatic green alga protist was the one organism that all plants are believed to have evolved from. The protists had chloroplasts, which made them like the land plants that developed later. Plants first evolved in the ocean, and are thought to have first colonized land 700 million years ago. The oldest fossils on land were 470 million years old. The first plants were nonvascular. Their biggest challenge to living on land was dryness and not being able to absorb enough water. One major adaption that developed in plants that allowed them to cope with this was having vascular tissues that helped carry water and minerals from the soil to the leaves for photosynthesis. Reproduction was challenging once plants moved on land because early vascular plants needed moisture for reproduction. Seeds made it possible to reproduce easier because they didn’t need water to reproduce. The first plants to evolve seeds were the gymnosperms. The next group of plants to emerge were angiosperms, which produced flowers and fruits, some of which attracted animals that dispersed their seeds. Flowers consist of male and female reproductive structures. Chaparral dodder is an angiosperm.
The origin of parasitism in plants shows a transition from an autotrophic (making its own food) to heterotrophic (getting food from host) lifestyle. To obtain nutrients from the host, plants developed haustoria, parasitic organs that invade the host’s tissues. Another important adaptation was the the plant’s ability to locate the host plant.
Dodder flowers may bloom as early as February to as late as October. In chaparral communities in Southern California dodder is parasitic on black sage, buckwheat, and deerweed. Dodder can survive about ten days without a host. Once the seedling attaches to its host plant, it taps into both the xylem and the phloem. Dodder rarely kills its host. Each dodder plant produces thousands of seeds, and the seeds can stay dormant in the soil for years. Dodder is the host plant of brown elfin butterfly larvae.
Morphology and Physiology
Chaparral dodder is an angiosperm, which means it is a plant that has flowers and bears fruits with seeds. Dodder flowers are clear and 3mm wide, and have five petals. Pollen is found on the anthers. When a bee or other animal comes to pollinate, the pollen sticks to the stigma. The pollen goes down the style, which forms a pollen tubule that allows the genetic material to reach the ovules. When dodder ovules get fertilized, the fertilized ovary develops into a fruit. The fruits are ⅛ inch wide, usually circular, light brown, and look like there is sugar on them. The fruits usually have one to four seeds. Chaparral dodder is a dicot, meaning it has two cotyledonary leaves when the seed first germinates. The reason why dodder doesn’t need leaves and has haustoria is because it is parasitic. Once dodder is attached to its host, it always wraps in a counter-clockwise direction. Dodder only has roots at the beginning of its life and later loses its leaves when they are not necessary. Dodder gets all of its nutrients by the haustoria attaching and pushing itself into the host plant. Haustoria are little structures that the dodder creates that pierce through the host’s vascular tissue. Dodder finds the host plant by "smelling," or detecting, chemicals in the air coming from the host. Dodder is herbaceous, meaning that there is no bark on the plant. Dodder is a vascular plant, meaning that it has a specialized conducting system that includes xylem and a phloem. The xylem carries water and nutrients and the phloem transports sugars and water upward to the stem. The phloem transports sugars to the leaves. The vascular bundles of the xylem and phloem are in a circular ring when the stem is viewed in cross section.
When dodder finds a suitable host plant, the stem coils around the host plant and makes tiny structures called haustoria that pierce through its host’s vascular tissue. When dodder latches onto its host plant, it taps into the xylem and phloem of the host. Dodder then begins to extract water and nutrients from its host, and the connection to the soil withers away.
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